Full support for the A570 implies numerous constraints for the CDTV developer. He has to worry about supporting a keyboard, working with different versions of the operating system, dealing with varying memory configurations and working around differences between Amiga and CDTV displays. The issues of starting, exiting, and multitasking titles remain. There are several Amiga/CDTV configurations that may be booted into a CLI or Workbench environment: Amiga + A570, any Amiga computer equipped with a CD-ROM, and a CDTV player with a floppy or hard disk attached. In these cases, the user may want to launch a CDTV title from that environment. If he does so, he will expect the title to exit cleanly, release all memory, remove any special assigns that may have been executed, etc. Users may even want to multitask a title. Most Amiga applications may be multitasked, and the user may well expect the same from a CDTV title. Reference titles would be significantly enhanced if they supported cutting-and-pasting directly into another application like a word processor. Those developing dictionary and encyclopedia titles may want to provide access methods for users or other applications to search on a key word. Some may even want to add an ARexx port. These issues, while reasonable requests from a user, add significant new burdens to the developer. Many CDTV titles are designed to take over the machine. Many of these titles require all the memory available in the system (and even more, in some cases). They often make special assigns for fonts, data, etc. Many include no clean-up code. Full compliance to AmigaDOS standards may be unreasonable for some titles. To address this problem, we have established three levels of compatibility for CDTV titles running on Amigas: Minimal Support, Support For Workbench Startup and Exit, and Full Multitasking Support. Level One-Minimal Support Level Two-Support For Workbench Startup and Exit Level Three-Full Multitasking Support