Inexplicably MicroStation does not have a select inverse function. YES you can use the inverse select mode in the Element Selection tool, but it is not the same thing as being able to select certain items, and engage a command that selects everything that had not been selected before and deselect what you had.Use this Key-In chainchoose element;powerselector area block;powerselector mode inverse;point absolute -999999,-999999,-999999;point absolute 999999,999999,999999;powerselector single;powerselector mode newI like to associate it with Ctrl+Shift+DataWhat it does is put the Element Selection tool into a block shape and inverse selection mode, data points to a negative coordinate hopefully well outside of your model's extremities, data points to the opposite positive coordinate, then returns the element selection tool to single and new mode! If needed you can add more 9s to the data point coordinates.If anyone has tips on making this command even more efficient I want to hear from you!