The design of programming languages that cleanly integrate concurrency constructs and object oriented features that promote software reuse is an open problem. We describe a design space that characterizes approaches to object-oriented concurrency in terms of a number of language design choices concerning the relationship between objects and concurrency. We identify requirements for sortware reuse and, with the help of an example that illustrates several of these requirements, explore the design space in order to evaluate which design choices interfere with reuse and which appear to adequately support it. We conclude by highlighting open research issues which, we believe, are essential for achieving effective reuse of concurrent software.