RonC wrote:
Or do you need to do these in 2 separate steps?
What version of SWX? I'll assume SWX 2004. It's seen as 2 separate constraints but can be assembled in one operation. Didn't you know that SWX has Alt+drag?

Click the Move Component command and click the SmartMates button in the browser. Double-click one circular edge and single click the mating circular edge. You should orient your components first because SWX "assumes" the mate/flush constraint based off of the part's current orientation. If it assembles backwards you have to edit both the coincident and concentric constraints and flip the solution direction (mate/flush).
I much prefer Adesk's insert constraint. SWX Alt+Drag does have a smoother, more animated, feel than IV's IMO.
Side note: What happened to Duke? What is that thing you have for an avatar now?
Hope this helps.