Mike,

1) AddProperty breaks OOP more than anything I've suggested.

2) the point is - and DAvid pointed this out - That the calling object and called object are going to have to know something about each other in order to communicate. Maybe at some point -we'll get good enough that an object can ask a mediator "gimme the price of a widget" and the mediator can figure out where to get that from and how the calling object wants it back. Until then - you are going to be coupled to a point and it is "pompous programming" to abstract things in the name of abstraction where there are no practical benefits to it.

Ken

>>Also - passingin a parm object doesn't completely decouple anyway - both the form and calling method still must make some assumptions about the structure of the object. Pick your poison!
>
>If the called object is supposed to fill in a property on the Parameter object that doesn't exist, it could easily do that with AddProperty(). Then you'll get the same object back every single time from the called object, instead of a modified version of the calling object which could be different every time.