In this chapter we explore ways to make a business case for the building of the CRM data warehouse. It is often said that it is not possible to cost-justify a data warehouse because we cannot tell what value the warehouse will bring. This is nonsense. The advice we should be giving to our customers and sponsors must be that, if you cannot justify the building of the data warehouse, then don't do it. Data warehouses are very expensive investments, just like new factories. We would not expect our bosses to sanction the building of a new factory simply because the manufacturing people thought it was a good idea, and we should take precisely the same attitude with a data warehouse.