No matter how fast systems become, many software applications continue to exceed the performance capabilities of the system they are hosted on at some point during their life cycle. There are two possible solutions to this problem. One is to purchase additional hardware. The other is to optimize the software. Each method has cost and schedule implications. Often, both additional hardware purchases and software optimizations are required. This chapter provides some general performance optimization guidelines that are applicable no matter which vendor's hardware or OS you are using. The examples presented, however, are specific to Sun's Solaris operating environment.