This document discusses return on investment (ROI) calculations for IT system projects. ROI is a measure used to compare the effectiveness of IT investments and can be used to justify projects. The basic ROI calculation divides the net return by the investment cost. Financial benefits include increased revenue, cost reductions, cost avoidance, and capital reductions. Non-financial benefits are also important but not included in ROI calculations. Factors like timeframe, consistency, and precision should be considered for accurate ROI analysis. Other relevant calculations discussed are net present value, internal rate of return, and payback period.