The Gobo Eiffel Time Library is a portable Eiffel class library covering date and time handling. When this library has been developed, there was no date and time library standard, and no portable library supporting the four main Eiffel compilers was publicly available. Each Eiffel compiler provides its own date and time library, but none of them is fully portable. Furthermore the existing date and time libraries only cover the absolute time and duration notions, leaving untackled areas such as time zones, stopwatches, clocks or timers. The Gobo Eiffel Time Library tries to address these issues with the same care that characterizes the other high-quality libraries that make up the Gobo Eiffel Project.