Abstract: A self-adaptive hybrid cache and method of caching data objects. A set of cacheable data objects is partitioned among a set of cooperating caches (e.g., a cache cluster). A hybrid cache is configured to cache data objects that it owns (i.e., objects in its partition) as primary content and to also cache data objects that are owned by other caches as secondary content (e.g., based on demand for such objects). A hybrid cache stores and/or removes objects based on criteria such as validity, popularity, size, age, cost of replacing, amount of available cache space, whether the objects are primary or secondary, etc. Over time, the amount or ratio of primary and secondary data that a hybrid cache stores may fluctuate dynamically.