The problem of scheduling activities in a project to maximize its net present value (NPV) has been solved recently for the case where net cash flow magnitudes are dependent on the time of realization. In this problem, incentive payments and penalties for early and late event occurrences respectively, as well as the cost of resources over time, are time dependent. We present a branch and bound solution approach for this problem. We compare the NPVs of the solutions obtained from the branch and bound algorithm with those of a simulated annealing approach developed earlier. Our computational results show that the branch and bound approach outperforms the best known simulated annealing implementation.