How many ERP SaaS offerings are in the market today? The number depends on who you ask but it is a fair statement to say that all Tier I and the majority of Tier II ERP vendors have a SaaS offering. A majority of the market and many ERP analysts still take an on-premise approach to evaluating ERP SaaS offerings. Services, not software, will have the greatest impact on ERP SaaS success. The purpose of this article is to examine the impact services will have in a SaaS model.