To find out the critical phase in the software environment that may be responsible for more defects than other phases involves the selection of a suitable decision making method for realizing the goal. Among analytical hierarchy process (AHP), fuzzy AHP and analytical network process (ANP), the latter is regarded as a viable alternative, which yields a holistic framework in the selection of the most critical phases in the presence of interdependencies. A practical case study concerning the software development for a financial application which involves the utilization of a tool driven approach like rational unified process (RUP) is made use of to demonstrate the effectiveness of ANP.