This paper reviews various approaches to package MEMS, illustrated mainly with examples from imec. Wafer-level or 0-level packaging is mostly dealt with. The role the package plays in achieving the required performance and reliability characteristics is elucidated. Package requirements, such as hermeticity and strength, are named, discussed and illustrated with examples. Considerations of reliability testing are presented. It is made conceivable that vacuum maintenance of tiny MEMS packages is a dominant reliability issue, something not at all obvious to achieve.