I would like to bind symbols to values, e.g, Q1=True, Q2=False.... and then allow the user to specify arbitary logical expressions like Q3 and Q4 or (given different bindings) Q2 == 5 It would be fine if they could execute arbitrary python scraps. It looks to me as if this might be a job for a PythonScript. I was going to evaluate an arbitrary string, but since PythonScript has a security and binding framework it seems better to use it. So I have two questions: 1) Is PythonScript the most appropriate tool? In particular, I am concerned because I am not calling it from the web, but from some code in my product. The API reference does not refer to this case as a possible use. 2) Exactly how do I bind the symbols for use within the script? In case you are wondering, I'm doing this for rules like "only answer question 5 if you said yes to questions 3 or 4". Thanks.