completed in a year or less. In either case, it is now time to plan in order to deploy in that time frame. Since Apache is the most popular Web server and PHP the most popular Web development tool, it is not necessary to demonstrate that the majority of normal Web applications can be built this way. A cursory search of the Web reveals large numbers of attractive and reliable applications that have been built using the open source tools (LAMP) and that there is a large body of people available who can develop and maintain these applications. Because of the fact that the Web is de facto an open source and LAMP playground, vendors of closed code systems usually focus on issues of scal- ability and enterprise integration to justify their products. This chapter will focus on those issues also. We will note that most needs fall comfortably in the range of performance of the open source products and that when neces- sary that performance can be increased through the appropriate techniques. Systems vary by their customer types, their performance requirements, and the type of information they manage and display. Applications that serve external customers will usually handle large and unpredictable num- bers of users. Of course, we have no control over their technology or behav- ior. Applications that service business to business (B2B) customers, such as channel, purchasing, or supply chain, can be as large in some cases as cus- tomer systems but should be more predictable, because we have a relation- ship with the customers that is more manageable. Internal sites should deal with predictable numbers of users, and quite often we can manage the tech- nology platform for internal users if we want to. Call center sites are the most manageable, since they are internal and we generally control the plat- form, installed applications, and the manner of use.