This thesis includes three essays. Title of essay number 1 is How Many Handicapped Parking Spaces Should There Be? In this paper we conducted an analytical study with a component of Monte Carlo simulation to determine the number of handicapped parking spaces that minimizes the average societal walking cost. Title of essay number 2 is Capacity Planning Analysis for Amazon.com Lockers. This essay investigates online shoppers' package retrieval behavior from an Amazon.com locker location and research its impact on capacity decisions at the Amazon.com locker locations. Essay number 3 is entitled Inventory Management Under Labor Constraints On Restocking. In this essay we will represent a linear programming model for determining optimal inventory stocking policies for a supermarket. After developing the conceptual model, we will use it to find inventory stocking policies under human resource constraints for a European grocery store.