TOC in Color
TOC in Color
| by Adail Muniz Retamal © July/2007 | Versão em Português |
“Just as the transition from black-and-white photography to color is so profound,
the transition from black-and-white modeling to color is an awesome one.”
The year was 2003. I’ve been researching and practicing Agile software development methodologies since 1999, but since 1992 I’ve been using Object-Oriented Programming in my software development practice. Of course, my natural next step at that early time was to start studying Object-Oriented Analysis and Design techniques to apply a common mindset to the whole development lifecycle. I’ve tried several methodologies, with varying degrees of success and satisfaction.
In 2003 I discovered FDD – Feature Driven Development, a complete Agile methodology for Agile Project Management and software development. FDD is a very clever blend of a solid Object-Oriented Software Engineering method, known as “The Coad Method”, named after Peter Coad, and a successful Project Management practice developed by Jeff De Luca, an Australian Project Manager.
But what FDD has to do with TOC? To me, a lot! First, it was at that very same time that I was presented to TOC by John Mac Felsing, co-author of “A Practical Guide to Feature Driven Development”, the FDD bible. But the point I want to make in this article is related to a technique that, although not mandatory or exclusive in FDD, makes a lot of sense and is extremely helpful: the UML in Color.
Peter Coad was (well, in my opinion still is) a very talented systems modeler, architect and strategist. He developed a couple of object-oriented software development methodologies, including processes, guides and graphical notations, back in the 80’s and 90’s. He also developed CASE (Computer Aided Software Engineering) tools to streamline and automate the modeling activities of a project team. His last and most famous modeling tool is called Together, now a product from Borland, since the acquisition of TogetherSoft (Peter’s company) in 2002.
After decades of modeling experience, in vast different business domains, he was hired in 1997 as the Chief-Architect for a challenging project in Singapore, where he proposed and tested the UML in Color technique. But more than coloring the UML, Coad also proposed the use of archetypes and described their common properties, behaviors and relationships.
After having more experience both with software models and TOC trees, I got the idea to apply the coloring technique to TOC Thinking Processes and, hence, the title “TOC in Color”.
Why use color?
I’ll let Peter and his colleagues answer this question for us. The quotations are from the “Color Book” and the emphasis are mine:
“Black-and-white conveys basic information. Color reaches out and grabs you.”
“In September of 1997, we started building models with four colors of Post-It notes: pink, yellow, green, and blue – one for each archetype. Developers and domain experts new to model building on the team commented a number of times along the way, 'But how could you possibly build effective models without color?' That caught our attention! So we developed this technique in practice, published initial findings, and presented this approach in an OOPSLA ’97 tutorial. As is often the case, practice preceded theory. Seeing these ideas work so well in practice, we began investigating color and why it appears to have such a profound effect on building better models.”
“Color gives us a way to encode additional layers of information. The wise use of color increases the amount of content we can express.”
“More importantly, one can use color to add layers of new content to models. Those layers are visible from a distance, so that ‘big picture’ model content comes across even before one starts reading the details. We call this effect ‘spatial layering;’ it means that a model is capable of delivering an overview and a detailed view all within itself, without needing to break visual context by jumping to some other representation. Color makes spatial layering possible.”
From what I’ve seen in my consultancy practice, when we stick the colorful trees to the wall we can easily see the broad picture, and the team can talk about it with much more confidence.
“The fundamental uses of color in information design are: to label (color as a noun), to measure (color as a quantity), to represent or imitate reality (color as a representation), and to enliven or decorate (color as beauty).”
I’ve been using colors when building TOC trees for all of those reasons:
To label: each color is a hint to the modeler and to the reader, like an archetype or stereotype (what is the kind of each entity in the diagram). This is a valuable extra information;
To measure: the colors can convey an idea of importance or priority, as in the case of the root causes and main UDE’s in the CRT (see below); another way that colors help measuring is the visual counting they enable on the spot (e.g., we have 3 pink root causes);
To imitate reality: enhancing the “tree” analogy, we’ll see that colors try to emulate the leaves, roots and trunks of the trees; we also have the “stop sign”, the injection (medicine in a syringe), etc.;
To decorate: of course, this comes as a bonus.
How many colors?
“Two or three colors are usually enough; five is too many. Four-color combinations must be selected with great care: nothing looks worse than too many colors, particularly when they lack common elements.” [Hideaki Chijiwa]
Given that 3M’s Post-It notes usually come in 4-color packages (of course, there are the mono-color packages as well), this is usually the maximum amount of colors used in building the models (the trees, in TOC).
Which colors?
“The perceptual-primary system, first proposed by Leonardo da Vinci, defines primary colors as red, yellow, blue, and green. These are the perceptual primaries, those colors that do not appear to have any other color in them.”
“We can mute these colors by adding a little white to them. That makes text placed on those colors much easier to read. So, for the four archetypes, we can use pink, pastel yellow, pastel blue and pastel green.”
This is very important: only use the pastel (light) tones of the colors, not the pure (strong) tones, otherwise your trees will look too much colorful and can irritate the readers!
CRT in Color
When constructing a CRT (Current Reality Tree), I use the colors to represent:
Green: the most visible UDE’s (the leaves of the tree);
Pink: the root causes (the roots of the tree);
Yellow: the intermediate UDE’s (the trunk and branches of the tree);
Blue: rarely used, but if some other information is needed, I use a blue box to show it (some assumption, for example).
The following picture shows a colorful CRT, typical for a software development and maintenance environment.
Notes:
The trees in this article may not be complete or accurate, for they may lack some thorough analysis with the Categories of Legitimate Reservation (CLR). They are meant for illustration purposes only.
I used Bill Dettmer’s version of the Thinking Processes, as stated in his book “Breaking the Constraints for World Class Performance”.

Figure 1: A CRT in color (click to see the large version)
We can quickly grasp what are the main UDE’s (the leaves) and root causes (the roots) of this tree. This scheme works very well when building CRT’s with a group of people, using Post-It notes stuck to a flipchart paper. The arrows are drawn on the paper using a permanent marker, after the group reaches a consensus on the cause-effect order.
But how do we know when a particular UDE will be a green, yellow or red one? Granted, we don’t know it beforehand. For that, I use the following process:
Initially, write all UDE’s with yellow notes and stick them to the paper.
After the logical analysis and group consensus, reorder the notes following the “causes at the bottom, effects at the top” rule, then draw the arrows.
For each UDE that doesn’t have any (or significant) arrows pointing to it, copy it in a pink paper and stick it replacing his yellow version. This is a root.
For each UDE that doesn’t point to any other UDE, or is pointed to by many other UDE’s, or is a well known situation in the context being analyzed, copy it in a green paper and stick it replacing his yellow version. This is a leaf.
If there is any other type of information you want to present together with the CRT (assumptions, comments, etc.), you can use a note of another color, like blue.
Clouds in Color
I often draw Evaporating Clouds diagrams directly on the flipchart or whiteboard, without using Post-It notes. However, if someone asks me to use the colorful notes, I would use green for the goal (A), yellow for the necessary conditions (B and C), and pink for the conflicting actions/desires (D and D’). The injections would be written in blue notes. The premises can be written right above or below the arrows, without boxes.

Figure 2: An EC in color (click to see the large version)
FRT in Color
For the FRT (Future Reality Tree), the basic color scheme from the CRT is used: pink for root causes, green for leaves, and yellow for the other UDE’s. The main difference here regards the blue color: it’s used to represent the proposed injections and predicted DE’s (Desirable Effects).
The image below shows a proposed FRT for the previous CRT.

Figure 3: An FRT in color (click to see the large version)
When modeling with a software tool (PowerPoint was used to build these diagrams), I distinguish the injections from the predicted DE’s with a different shape of the box (the injections are squared rectangles). With Post-It notes, I write “INJ” at the corner of the blue note to denote an injection.
NBR in Color
The NBR (Negative Branch Reservation) tree is actually a complement to an FRT, usually built after someone expresses a potential risk in the proposed solution. Thus, this risk is a “red sign” of warning, and is written in a pink note. The injections, as usual, are blue. I use green to denote a desirable state or effect, and yellow for the other real life facts and states.

Figure 4: An NBR in color (click to see the large version)
PRT in Color
The PRT (Pre-Requisite Tree) is treated differently from the previous ones, because it is somewhat different. We basically have obstacles, actions and the objective.
Let’s start with the objective: it’s a lonely blue box at the top (because, usually, it’s an injection from the FRT). An obstacle is drawn as a “Stop sign” (which is a red octagon), thus, it’s pink. The actions (like the “Go” sign), are green.
When constructing a PRT with Post-Its in a group, start by sticking the blue objective/injection at the top of the flipchart paper. Then ask the group for the pink obstacles. Finally, ask for the green actions that will overcome the obstacles. Put the actions in logical and chronological order, draw the connecting arrows and, voilà, you have a portion of a project network to be executed, using Critical Chain Project Management, of course.
The following image shows a PRT for one of the injections at the previous FRT.

Figure 5: A PRT in color (click to see the large version)
TT in Color
The TT (Transition Tree) is another way to communicate the proposed plan as in the PRT. The focus of TT is to explain the why, along with what to do. Here I present the same PRT content, now translated into a TT.
As in CRT and FRT, the most visible leaf/objective (desidered state) is written in a green note and put at the top of the paper. The initial conditions, usually UDE’s, are written in pink notes. Then we have a series of trios composed of a state, a need and an action. The intermediate desired states are also written in green notes, the actions (here they are injections) are blue, and the needs are yellow.

Figure 6: A TT in color (click to see the large version)
Summary
I hope this brief explanation of how I’ve been using color when constructing TOC trees will help you in your future adventures.
The following table summarizes how the colors are used with each tree.
| Pink | Green | Yellow | Blue | |
| CRT | Root Cause | Main UDE | UDE | Assumption, etc. |
| EC | D, D’ | A | B, C | Injection |
| FRT | Root Cause | Main DE | DE | Injection |
| NBR | Risk | DE | Fact, UDE | Action, Injection |
| PRT | Obstacle | Action | - | Objective/Injection |
| TT | Initial State | Objective, DE | Need | Action |
From my experience, using color in my models, both in software systems and TOC trees, helped me enhancing the thinking process and better communicating with other people. As a consequence, the time and effort required to build the diagrams are shorter, and amazingly, the quality is much higher.
I used PowerPoint to draw the trees in this article, but I know that it is not the best tool for the job. Basically you can use almost any drawing tool available. I’ve also tried Visio, Transformation Logic Tree (TLT) and Flying Logic.
Unfortunately, the last version of TLT I used (Beta 0.8.8) does not yet support colors in the boxes. Thus, I use TLT to draw a tree and then I copy and paste it into PowerPoint, to apply the appropriate colors. It’s not a very efficient job, but I can leave with it while waiting for the color support in TLT.
The Flying Logic tool is very interesting as well. It automatically spreads the entities around the screen and has a very beautiful design. It also offers the possibility to test the logic of the trees.
I thank Peter Coad and his colleagues for creating the UML in Color technique, and I hope many of you in our TOC community will take this seminal work much further than what was presented here.
Now, grab your Post-It notes and start coloring your trees!
About the Author
Adail Muniz Retamal is CEO at Heptagon TI Ltda (www.heptagon.com.br), a Brazilian company dedicated to consulting, training, coaching and mentoring in TOC and Agile software development methodologies. He graduated as an Electronics Engineer in 1993, but since 1983 he has been a software developer, analyst, architect, project manager and instructor. He is the founder and moderator of TOC-Brasil, the Brazilian Yahoo group for TOC, and GUFDD, the Brazilian Yahoo group for FDD. Adail can be contacted at "adail at heptagon.com.br".
This article can be copied, translated and published only in its entirety, including this note. The author will appreciate a notification to keep tracking of where it is published.
This article was featured on Goldratt Marketing Group's TOC Update Newsletter of October/2008
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