Persistent programming is concerned with the creation and manipulation of data with arbitrary lifetimes. This data is often valuable and therefore protected to ensure that it is free from misuse. The mechanisms used to protect the data vary with a tradeoff between static expression of the protection and the flexibility in modelling it. In this paper we explore the full range of protection mechanisms in persistent systems from static to dynamic checking and contrast it with the corresponding balance between safety and flexibility in the system. Protection by capabilities, dynamic universal union types, encapsulation, subtype inheritance, existential quantification and predicate defined invariants will be explored with reference to manipulating long lived data.