Comparing Software Acquisition Models Against Each Other: The "Build" vs. "Buy" vs. "Rent" Trade Study

Abstract

Software can currently be acquired in three different methods. The first is to have software custom built/developed to match a particular specification/requirement. We shall refer to this option as "make". The second is to purchase a software product from a vendor/supplier. We shall refer to this option as "buy". The third is to rent/outsource the use of a software product or a software development environment from a third-party supplier. We shall refer to this option as "rent". It seems that what is lacking is some guidance to help acquirers decide which of these three software acquisition approaches to consider and, eventually, to select. This lack of objective, quantitative guidance (including risks associated with each option, decisions needed for each option, etc.) causes acquirers to sometimes make ill-informed decisions about which acquisition method to use. This paper identifies some of the differences between these three acquisition models as mapped against several life cycle phases and project activities, and then identifies risks associated with the "rent" option.