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In previous work we defined respects for immutable types A, B, and T; in this paper we extend our notion to handle conversions between mutable types. This extension is non-trivial since we need to consider an object's behavior as it varies over time. We present in detail two examples to illustrate our ideas: one for converting between PNG images and GIF images and another for converting between different kinds of bounded event queues. We also discuss in less detail other real-world applications, namely those inspired by our Typed Object Model (TOM) conversion service built at Carnegie Mellon and by the infamous Year 2000 (Y2K) problem.