PROCESS

The Process series grew out of Casey Reas’ commission for the Whitney Museum of American Art’s online portal, Artport. In 2001, curator Christiane Paul invited Reas to create Software Structures, an online artwork linking conceptual art to emerging software practice. Responding to Sol LeWitt’s instructional wall drawings, Reas created Structure 1–3, three texts that translated LeWitt’s logic of written scores into generative systems.

In LeWitt’s work, the instructions are primary, and the wall drawings are realizations of those rules. For Process, Reas extended this principle into software. His programs were written as code, but once executed, they could run indefinitely to produce an endlessly variable array of images. In this way, the artist’s role was not to compose pictures, but to define systems.

Software Structures marked a turning point in Reas’ understanding of the relationships between 1960s conceptual art and twenty-first century generative art. It clarified how conceptual strategies could fuse with computational execution, and it seeded the method that would become Process: systems stated as rules, enacted by software, and capable of generating both specific outcomes and an open field of potential images.

Forms, Behaviors, and Elements

The core of the Process series is a grammar of Forms, Behaviors, and Elements. A Form is a visual primitive like a line or circle. A Behavior is a rule for action, like “move in a straight line.” An Element is a Form paired with one or more Behaviors to create a simple machine.

For example, Element 1 is defined as:

Element 1: Form 1 + Behavior 1 + Behavior 2 + Behavior 3 + Behavior 4

Form 1: Circle

Behavior 1: Move in a straight line
Behavior 2: Constrain to surface
Behavior 3: Change direction while touching another Element
Behavior 4: Move away from an overlapping Element

Placed in an environment, Element 1 moves independently, responding to encounters with other Elements. When implemented in software, the system evolves step by step: at each moment, every Element modifies itself according to its Behaviors, and the cumulative traces of these adjustments generate the visual forms.

Although the systems are coded in software, Reas made a deliberate decision to also present them in English-language instructions. Each Process is a short text that defines an environment, and leaves many decisions open to interpretation. In this way, a Process can be enacted through software, drawing, or other means. Presenting the rules in English places the series in dialogue with conceptual art’s scores and instructions, while also making the work legible beyond the domain of programmers.

This choice underscores that the text is primary: the rules are the artwork, while software and hardware are secondary interpretations that can shift over time. To implement a Process in code is itself an act of interpretation, requiring the artist-programmer to make choices not specified in the text. Hardware, too, is incidental—fragile and replaceable—while the instructions endure as the work’s essence.

Process 4–18

Between 2004 and 2010, Reas developed the central arc of the series, from Process 4 through Process 18. Each work in this series specifies a set of Elements, plus rules for rendering their interactions. The logic is minimal, but the results are expansive, ranging from sparse networks to dense, layered fields.

Process 6 (image 4), 2005.

A representative early work is Process 4:

A rectangular surface filled with varying sizes of Element 1. Draw a line from the centers of Elements that are touching. Set the value of the shortest possible line to black and the longest to white, with varying grays representing values in between.

Here, adjacency becomes connective drawing. Contact between Elements is registered as a center-to-center line whose tone encodes distance: short connections are dark, long ones are pale, with gradations between. The surface resolves into networks of varying tonal weight, as nearby Elements are marked by strong black lines, and distant contacts are marked by lighter traces. Depending on initial conditions, the system produces delicate lattices or densely interwoven structures.

Installation view of process 11 at bitforms gallery in seoul, 2007.

Installation view of process 4 in FEEDBACK at Laboral Centro de Arte. Gijón, Spain. 2007.

By contrast, Process 18 shows how far the grammar can be pushed toward saturation:

A rectangular surface filled with instances of Element 5, each with a different size and gray value. Draw a quadrilateral connecting the endpoints of each pair of Elements that are touching. Increase the opacity of the quadrilateral while the Elements are touching and decrease while they are not.

Rather than lines, Process 18 generates translucent planes. When Elements touch, quadrilaterals connect their endpoints; their opacity grows with continued contact and fades as the connection breaks. Over time the image builds into interlocking fields that oscillate between open scaffolds and dense, tessellated surfaces. Where Process 4 emphasizes legibility, Process 18 demonstrates the system’s capacity for overwhelming density and emergent complexity.

Process 18 (Image A 5, 6). 2010.

Across Process 4–18, the series spans this spectrum—from diagrammatic clarity to saturated fields. Each work begins from the same grammar of Forms, Behaviors, and Elements, yet the outcomes vary widely depending on how rules are combined, scaled, and rendered. Over six years, the series evolved from spare networks to dense, tessellated surfaces, establishing a body of generative drawing systems that defines the core of Process.

TI and Surface

With TI (2004) and Surface (2009), the Process series expanded from the screen into the room. These installations reorient the series toward immersion, transforming computational images into spatial experiences. Similarly, they demonstrate how generative form can unfold across architectural surfaces, turning the act of viewing into one of bodily navigation and orientation.

Installation view of ti in natural at bank. los angeles, ca. 2005.

While installed, TI was projected onto circular disks scattered across the floor, bringing the work to body scale. Its imagery moved with a slow, fluid rhythm, growing from the center and dissolving toward the edges. Viewers walked among the disks, encountering luminous forms that hovered between synthetic design and organic life—an environment that was as much experienced physically as it was seen visually.

Surface extended this approach by arranging twenty equilateral triangles as a Dymaxion map, recalling Buckminster Fuller’s vision of the globe unfolded. Each triangle carried a distinct iteration of the Process software, producing a faceted field that suggested a massive or micro scale. The fractured geometry amplified the tension between natural flow and artificial structure, embedding organic motion within a cartographic and architectural frame.

Process Compendium

The culmination of the Process series is the Process Compendium (2010), realized as two sets of fifteen prints each. Both sets—labeled A and B—contain one print for every Process work created to date. Each print also pairs two images generated from the same Process text, emphasizing that the text is not a prescription for a single outcome, but rather a generator of unlimited variations. By presenting two realizations side by side, the sets make visible the range of possibilities within each system: no image is definitive, and every Process text unfolds as a field of potential outcomes.

Process 7 from process compendium a and b, 2010.

Process 18 from process compendium a and b, 2010.
The two sets of prints are augmented by the Process Compendium catalog, which extends the archive into book form. The publication reproduces the prints alongside the English-language instructions for each Process, plus alternate software interpretations by different programmers, and time-lapse sequences that show forms accumulating over time. Together, the prints and book reinforce the project’s central premise: that the artwork resides in the rules themselves, while any given image is only one among countless possible interpretations.

The Process Compendium preserves the series as both visual record and conceptual framework. It stabilizes a decade of generative systems while keeping their openness intact, presenting the rules as enduring structures and the images as provisional realizations. At the same time, it set the stage for Pre-Process, where the underlying grammar of Forms, Behaviors, and Elements is revisited and expanded in a new context.

Pre-Process

The ideas behind Pre-Process first emerged in 2003 and were shown in partial form at the exhibition Process/Drawing (bitforms, 2005). At that stage, the work existed as a collection of unresolved software sketches—experiments that were never offered for sale, but served as the foundation for what became the Process Compendium. Over the following years, Reas refined the system of Forms, Behaviors, and Elements into the fully articulated Process series, yet the early Pre-Process code remained a touchstone, marking the point where the method first cohered.

stills from Pre-Process, 2022.
Nearly two decades later, in 2022, Pre-Process was completed and released on the digital platform Art Blocks as a curated project. Reas has described this release as the “Rosetta Stone” of his practice, as it clarifies the origins of Process while adapting the core systems to a new cultural and technological context. The edition consists of 120 unique works, each defined by the combination of three axes of variation: the way Elements are rendered (the “surface”), where they originate (center, line, or random positions), and their relative sizes. Eight surfaces × three origins × five sizes establish the finite but expansive space of the project, making every edition a distinct realization of the same underlying system.

Reflecting on the work, Reas observed, “The authorship is in creating potential for variation and difference.” This perspective situates Pre-Process not as a fixed artwork, but as a field of possibilities that reveals the continuity between the early sketches of 2003 and the distributed frameworks of blockchain-based generative art. By completing a work first drafted nearly twenty years earlier, Reas connects the origins of his practice to the evolving forms of contemporary generative art, showing how systems written in 2003 can still unfold into new aesthetic and cultural spaces.

Reception and Impact

The Process works have been widely exhibited and collected, with appearances at major institutions including the Whitney Museum of American Art, the San Francisco Museum of Modern Art, the Centre Pompidou, and the Victoria and Albert Museum. They have been presented internationally in exhibitions that situate them within both the history of generative art, and the wider field of contemporary digital practice.

Installation view of Structure 3A and 3b (left) in Programmed: Rules, Codes, and Choreographies in Art, 1965–2018 at the whitney museum of american art, 2018.

The project extends the lineage of generative art from the 1960s, while articulating the translation into real-time software art that is distinct to the early twenty-first century. By translating programming notation into English instructions, Process reconnects computational systems to conceptual art’s textual strategies. It also demonstrates how software-based art can inherit and transform this tradition to render it newly legible in a digital era.

Critically, Process is regarded as one of the most comprehensive articulations of generative art in the early twenty-first century. Its development coincided with the creation of Processing, the open-source programming environment that Reas co-created with Ben Fry in 2001. The works exemplify Processing’s ethos of clarity and accessibility, showing how simple systems can generate complex results, and how the logic of software can be made legible to artists, students, and general audiences alike.

The publication of the Process Compendium catalog clarified the importance of the text. By pairing the English-language instructions with the corresponding images, it reinforced the project’s conceptual transparency and extended its reach beyond galleries into classrooms and libraries. The catalog positioned the series not only as a body of works, but also as a method that was available for re-enactment, teaching, and adaptation.

Rules as Form

The Process series is at once an archive of works and a model for thinking. Each piece crystallizes a system of rules into visual form, yet the rules always imply more possibilities than can ever be shown. Its legacy lies in the insistence that minimal instructions can yield complexity, and that translating code into English is itself a generative act. In this way, the images are records of systems unfolding; they are not conclusions, but rather traces of ongoing processes.

Through prints, software, and publications, Process established a foundation for contemporary generative practice. It revealed how clarity of instruction and openness of execution can coexist, and how computational art can be both systematic and surprising. Seen today, Process endures as a landmark: a synthesis of conceptual instruction and computational execution, a decade-long exploration of rules as form, and a demonstration of how procedures themselves can be works of art.

Related Artworks
Browse the Process category on the REAS INDEX.

Further Exploration
Burnham, Jack. Software, Information Technology: Its New Meaning for Art. Exhibition catalogue. New York: Jewish Museum, 1970.

LeWitt, Sol. “Sentences on Conceptual Art.” 0 To 9 3 (1969): 3–5. Reprinted in Art-Language 1, no. 1 (May 1969): 11–13.

McShine, Kynaston, ed. Information. Exhibition catalogue. New York: Museum of Modern Art, 1970.

Nees, Georg. Generative Computergraphik. Stuttgart: Studiengesellschaft für Kybernetik, 1969.

Reas, Casey. Process Compendium 2004–2010. Los Angeles: Reas Studio, 2010.

Reichardt, Jasia, ed. Cybernetic Serendipity: The Computer and the Arts. Exhibition catalogue. London: Studio International, 1968.

Whitney Museum of American Art. “{Software} Structures.” Artport. 2004. Accessed August 27, 2025. https://whitney.org/exhibitions/software-structures.

Selected Exhibition History
Programmed Expressionism. Nguyen Wahed and DAM Projects. London, UK. 21 – 27 November 2024. Process Compendium prints 13 and 16. [E-24-08]

Digital Witness: Revolutions in Design, Photography, and Film. Los Angeles County Museum of Art (LACMA). Los Angeles, CA. 24 November 2024 – 13 July 2024. Process 14. [E-24-06]

In Our Code. Unit. London, UK. 13 September – 16 October 2022. Process Compendium (X-4), (X-5), (X-6).

Mimèsis. Un design vivant. Centre Pompidou-Metz. Metz, France. 11 June 2022 – 6 February 2023. Process 13. [E-22-04]

Cartography of the Mind. Christie’s. New York, NY. 21 – 28 June 2022. Process Compendium (X-6). [E-22-02]

Design & the Wondrous: On the Nature of Ornament. Centre Pompidou x West Bund. Shanghai, China. 12 November 2020 – 28 February 2021. Process 13. [E-20-06]

Chance and Control: Art in the Age of Computers. Victoria and Albert Museum. London, UK. 7 July – 18 November 2018. Process 18 (Software 3). [E-18-06]

Process. BCA Center. Burlington, VT. 9 March – 28 April 2012. Process 18 software with related prints and objects, Process 16 (Software 3), Network B. [S-13]

Process Compendium 2004–2010. Gallery [DAM] Berlin. Berlin, Germany. 10 September – 3 November 2010. Process Compendium archive prints and selection of Process 18 prints. [S-12]

Transfers and Actions. Mejan Labs, Royal Academy of Fine Arts. Stockholm, Sweden. 15 April – 7 June 2009. Process 18. [S-11]

Code and Form. Pittsburgh Center for the Arts. Pittsburgh, PA. 7 February – 19 April 2009. Works from the Process series. [S-10]

Process / Form. bitforms gallery. New York, NY. 6 March – 12 April 2008. Debut of new work from the Process series. [S-09]

Microstates. James Edward Carlos Gallery, University of the South. Sewanee, TN. 16 November 2007 – 9 January 2008. Process 14 and 18. [S-07]

Casey Reas and Suzung Kim. bitforms gallery. Seoul, Korea. 15 December 2006 – 27 January 2007. Debut of new work from the Process series. [S-06]

World on a Wire. bitforms gallery. New York, NY. 28 June – 3 August 2012. Curated by Laura Blereau. Process 18 prints. [E-12-05]

Field Conditions. San Francisco Museum of Modern Art. San Francisco, CA. 1 September 2012 – 6 January 2013. Debut of Process 18, 2012. [E-12-07]

Multiversités Créatives. Centre Pompidou. Paris, France. 3 May – 6 August 2012. Process 13. [E-12-06]

Random Access: Data as Art. Montserrat Gallery, Montserrat College of Art. Beverly, MA. 3 February – 31 March 2012. Process 14 (Software 3). [E-12-03]

Seeing/Knowing. Graham Gund Gallery, Kenyon College. Gambier, OH. 29 October 2011 – 4 March 2012. Process 18 (Software 2), Process 18 (Object 1, 2), Process 4 (Installation 3). [E-11-04]

Process as Paradigm. Laboral Centro de Arte y Creación Industrial. Gíjon, Spain. 23 April – 27 September 2010. Curated by Susanne Jaschko and Lucas Evers. Process 18 software with objects and prints. [E-10-02]

Decode: Digital Design Sensations. Victoria & Albert Museum, Porter Gallery. London, UK. 8 December 2009 – 11 April 2010. Exhibition subsequently presented at the Museum of CAFA in Beijing, The Garage Center for Contemporary Culture in Moscow, and the Design Museum Holon. TI. [E-09-11]

Art + Electronic Media. bitforms gallery. New York, NY. 18 June – 10 July 2009. Process 8 (Image 1). [E-09-06]

Abstract Cinema. Museum of Contemporary Art, North Miami. North Miami, FL. 26 March – 10 May 2009. Curated by Bonnie Clearwater. Process 16. [E-09-03]

Scalable Relations. Beall Center for Art + Technology. Irvine, CA. 9 January – 14 March 2009. Curated by Christiane Paul. Process 16. [E-09-01]

Media Cabaret at the Philadelphia Live Arts Festival. Philadelphia, PA. 29 August – 13 September 2008. Curated by Lars Jan. Process 14 and Process 16 as large, ambient projections. [E-08-09]

Holy Fire. iMAL Center, Brussels. 18–30 April 2008. Curated by Yves Bernard and Domenico Quaranta. Process 5. [E-08-06]

Scriptedbypurpose. FUEL Collections. Philadelphia, PA. 7–20 September 2007. Curated by Marc Fornes and Skylar Tibbits. Process 8 (Image 2) and Process 14. [E-07-06]

Summer Group Exhibition. bitforms gallery. New York, NY. 25 May – 20 June 2007. Process 11. [E-07-05]

FEEDBACK. Laboral Centro de Arte. Gijón, Spain. 30 March – 30 June 2007. Curated by Christiane Paul. Debut of Process 4 (Installation 1). [E-07-02]

Design Life Now: National Design Triennial. Cooper-Hewitt, National Design Museum, Smithsonian Institution. New York, NY. 8 December 2006 – 29 July 2007. Traveled to ICA Boston (Sept 2007 – Jan 2008) and Contemporary Arts Museum Houston (Jan – Apr 2008). Process 6 (Image 4). [E-06-12]

Cybernetic Sensibility. Daelim Contemporary Art Museum. Seoul, Korea. 26 October 2006 – 21 January 2007. Process 6 (Image 3). [E-06-11]

Texelectronica. UNT Fort Worth ArtSpace. Fort Worth, TX. 26–28 October 2006. Debut of Process 9 (Installation 1). [E-06-10]

Further Processing. Kunstverein Medienturm. Graz, Austria. 23 September – 11 November 2006. Curated by Marius Watz. Process 9. [E-06-09]

La Noche en Blanco. Madrid, Spain. 23 September 2006. Process 7 projection. [E-06-08]

Second Natures. University of California, Los Angeles. Los Angeles, CA. 14 September – 26 October 2006. Faculty exhibition curated by Christiane Paul for the opening of the Broad Art Center. Process 4. [E-06-07]

Swarm. Fabric Workshop and Museum. Philadelphia, PA. 3 December 2005 – 18 March 2006. Process 4, Process 6 prints. [E-05-14]

Moving Pictures: Digital Paintings. The Dallas Center for Contemporary Art. Dallas, TX. 4 November – 23 December 2005. Process 4. [E-05-13]

Bioart. Gallery António Prates. Lisbon, Portugal. 23 September – 18 October 2005. Process 6 software and prints. [E-05-12]

Generator.x. National Museum for Art, Architecture and Design. Oslo, Norway. 24 September – 16 October 2005. Curated by Marius Watz. Process 8 (Software 2). [E-05-11]

Thick Works. School of the Art Institute of Chicago. Chicago, IL. 16 August – 28 September 2005. Thick Process 5. [E-05-10]

Process / Drawing 2. Gallery [DAM] Berlin. Berlin, Germany. 2 October – 23 November 2005. Process 6 and related prints, debut of Process 7. [S-04]

Process / Drawing. bitforms gallery. New York, NY. 4 March – 3 April 2005. Debut of Process 4, 5, 6 software and related prints. [S-03]