Most brands that commission illustrations get a batch of assets, not a system. The difference shows up six months later, when the third illustrator on the project produces work that technically matches the original style sheet but reads as a different visual language. Building a system means solving that problem before it happens.
What Makes a Set of Illustrations a System
A system has constraints that hold, not preferences that drift. The defining difference between a collection of illustrations and a system is whether someone new can produce work that belongs, without being supervised.
That requires three things: a defined style vocabulary (how marks get made), a color contract (which values from the brand palette apply and how), and a set of reusable primitives (shapes, textures, motifs) that carry across every piece. Without all three, what looks consistent when one person is doing the work will fragment the moment it gets handed off.
Setting the Style Vocabulary
Style decisions are the foundation. The choices that need to be explicit:
- Line weight and stroke treatment (single weight vs. tapered; closed vs. open fills)
- Perspective convention (flat, isometric, oblique, loose 3D)
- Character treatment, if figures appear (realistic, geometric, silhouetted)
- Texture approach (solid fills, hatching, grain, none)
- Shadow and lighting rules
Each of these has to be a choice, not a tendency. “We use flat illustration with a slight texture” is not a rule that survives handoff. “All fills use the brand palette at 100% opacity; no gradients; halftone grain overlay at 15% opacity on surface fills” is.
The temptation is to keep style rules vague to give illustrators creative room. The result is a visual language no one can reproduce. Specificity is what makes a style transferable.
The style vocabulary also needs to account for what the illustrations are actually for. A system built around full-page editorial scenes works differently from one built around small UI spots. The range of intended formats shapes the rules. If you’re also building an icon set alongside illustrations, read about iconography for brands before deciding where one vocabulary ends and the other begins. The distinction matters: icons usually need stricter constraints at small sizes, and the two systems can share a color language without sharing a drawing style.
Building the Color Rules
The illustration palette is almost never a new palette. It’s a specific subset of the brand’s existing color system, with rules about which values apply to which roles: background fills, object fills, linework, highlights.
The failure mode is treating illustration color as independent creative territory. That produces work that feels visually competent but off-brand, particularly in digital contexts where illustrations sit directly next to UI components. The brand color system has already done the work of sorting values and contrast relationships. Illustration rules should extend that, not bypass it.
Practical rules to define:
- Which palette values are available for object fills, and which are off-limits
- Whether white is a “real” fill or just the absence of fill
- The maximum number of distinct colors in a single scene
- How to handle black (eliminated entirely, softened to near-black, or reserved for linework only)
Assembling the Primitive Library
Before producing finished illustrations, build a primitive library: the recurring shapes, objects, and motifs that will appear across multiple pieces.
For most brands, this includes common object “props” relevant to the brand category, a repeating geometry or texture used as background treatment, a small set of character archetypes if people appear, and standard environmental elements like ground planes or architectural fragments.
Building the library first is what makes extensions fast. The fourth illustrator on the project can work from primitives, not from scratch. The exercise also surfaces gaps: if the style rules can’t generate a coherent primitive for a common use case, the rules need revision before production scales.
Where Most Systems Break Down
Two failure points come up consistently.
The first is insufficient documentation. Style sheets that only show finished illustrations are not enough. Illustrators working from examples alone will reproduce the surface qualities without understanding the rules behind them. The documentation needs to show decisions, not just outputs: stroke weight in points, hex values in context, layering order in the working files.
The second is over-ambitious scope at the start. Trying to define rules for every possible output upfront produces systems so complex that nobody uses them. Start with the two or three formats that actually ship first (hero scenes, spot illustrations, background patterns), build and document those, then extend. An illustration system used at 60% coverage is more valuable than a complete spec nobody follows.
Build for the formats you need now. The system grows cleaner by being used, not by being specified in advance.
The relationship between the illustration system and the logo is worth settling early. Not every context calls for both; some applications need the wordmark, some need an illustration, and some need neither. That distinction belongs in the brand guidelines alongside the logo design process documentation, so the two parts of the visual language are positioned together rather than defined in isolation.
How Strynal Approaches Brand Illustration
Building a brand illustration system is a phase within a visual identity engagement, not a standalone deliverable. The style vocabulary, color contract, and primitive library all depend on decisions made earlier in the brand process. Positioning, color, and the brand typography system all need to be settled first. Starting illustration work before those foundations are stable means building the system twice.
At Strynal, illustration work happens as part of brand identity engagements. We define the constraints before anyone draws a line and build the primitive library before producing finished assets. The deliverable is not a folder of illustrations. It’s a documented system that another designer can extend without asking questions.
If you’re working through a full visual identity and wondering where illustration fits, get in touch.