A method of testing software uses a debugger and a breakpoint handler. The debugger inserts a breakpoint in a target application and enters at least one filtering condition associated with the breakpoint in a data structure. When during execution the target application encounters a breakpoint at an address, the target application transfers execution to the breakpoint handler. The breakpoint handler uses the address to retrieve filtering conditions from the data structure, executes code for evaluating the filtering condition, and transfers execution back to the target application if the filtering condition is not met.