I have looked at the BGL User Guide/Reference manual book but I can't seem to find the answer to this seemingly basic question. I have a directed BGL graph. Given two vertices U and V, I want to know whether there is a path from U to V. I don't care what path it is; I just want to know whether one exists or not. It looks like I might be able to use the BFS or DFS to do this, but that seems like attacking a mosquito with a tank. A slightly more complicated problem that I want to solve is: given vertices U and V, I want to know whether there is a path from U to V such that all edges along the path have a certain property. Again, I don't care to know what the path is or its length; only whether or not such a path exists. Thanks in advance, David Jones