One of the problems facing any person trying to implement MBSE into an organisation is one of the biggest issues that the authors have experienced. It is not the technical side, nor is it having the tools in place, nor the training. Perhaps the single biggest hurdle is one that can kill any initiative before it has even begun, and this is selling MBSE or, to put it more accurately, conveying the benefits of MBSE to relevant Stakeholders within the business. A common pitfall at this point is to go to the Internet and to perform a search on `benefits of MBSE' which seems both obvious and intuitive. The downside of this is that, invariably, all of the first hits will be from tool vendors who will essentially state the capabilities of their tools. There is nothing wrong with this per se, but these capabilities will typically excite Systems Engineers, but may not necessarily excite the people who have responsibility for budgets in the organisation. The key thing to bear in mind here is that different Stakeholders will look for different benefits from MBSE because, you have guessed it, they each have their own context. It is essential to understand the “why”of each Stakeholder Role. If we cannot understand their “why”, then we have failed before we have begun. In order to illustrate the benefits of MBSE, we shall be using a simple analogy of “the old lady who swallowed a fly”which is a traditional nursery rhyme in some parts of the world. If you are not familiar with this children's verse, then stop reading, get on the Internet and search it out. The chapter will make a lot more sense if you do this!