Mechanisms for storing and searching a hierarchy of policies and associations thereof are disclosed which may be particularly useful for implementing security protocols, such as, but not limited to Internet Protocol security (IPsec). For example, a hierarchy of policies is stored in a search priority order in an associative memory, with each association of a particular policy stored higher in the search priority than its associated policy and after any other policy. Therefore, a lookup operation on the associative memory will identify a matching association, if one, else its matching policy. A match of a policy instead of an association may result in a corresponding association being added in the appropriate location. For IPsec implementations, the lookup word is typically derived from the packet, with this packet being typically processed based on the identified policy or association.