Externalizing Business Rules

For the last 6 months have been working on a project which has a rule engine at its core. Needless to say the business processes are such that a lot of decisions have to be taken based on rules. Today came across a second article advocating the externalization of rules. I am referring to James Taylor's blog post titled "Here's how decision management simplifies process management"
I have borrowed the simple diagram he has used to show the externalization of business rules.



No doubt the diagram on the right looks much simpler and purely shows the flow. Although it no longer tells the viewer on how the decisions were made.

The first post that I am referring to, is a post by Bruce Silver. It came up as a part of my watch on BPMN 2.0. In his post called "5 Things to Love About BPMN 2.0" one of the points mentioned is the introduction of a "Business Rule Task" as a part of the BPMN 2.0. Here is the line that i would like to quote:

A major problem has always been that tools have not had a way to properly represent business rules in the process diagram. (I am not talking about routing logic embedded in gateways. Both the business rule and BPM communities, when they are on speaking terms, now agree that these are not what we mean by business rules.)

I am still trying to figure out how BPMN 2.0 will manage to do this. True enough, the gateways provide enough power to let me represent the flow (routing) after a decesion on has been taken. Never really got to use the complex gateway, which I had long assumed is meant for this exact purpose. Here is how it is supposed to function:

Each Decision Gate is associated with a condition expression found within an outgoing Sequence Flow. When a Gate is chosen during the performance of the Process, the corresponding Sequence Flow is then chosen. A Token arriving at the Decision would be directed down the appropriatepath, based on the chosen Gate.

What my tool provides is something like this:


Talking of the BRMS producs, the way a rule is captured is completely different. The best of the breed (whether ILOG or Corticon or the rest mentioned Leaders by research firms like Gartner and Foresstor) provide a way to frame up the rule in the form of tables or IF then Else constructs.

While I wait to see what BPMN 2.0 prescribes, I really think the primary users of my process models, "the business users" should still be able to easily understand what is happening by looking at the visual model.

The next best thing probably would be if the tool allows me to publish the process flows such that the emebeded rules are intutively made visible to the user while viewing the flows. May be a pop up/tool tip every time I place my cursor on the outgoing sequence flow from the gateway.