the paper's title: Capsule author's names: Robert C. Martin email address: rmartin@oma.com postal address: 14619 North Somerset Circle, Green Oaks, IL, 60048 phone number: 847.918.1004 a 100-word abstract: (below) the subject area of the paper: Dependency Management 2 or 3 keywords that will help characterize your paper: Cross-Casting, C++, dependency Abstract: Sometimes you need the lowest levels of your application to communicate with the highest levels, without the intervening levels knowing much about that communications. For example, the functions at the lowest software levels may experience errors that they need to communicate to the topmost layers. If these errors require complex data structures to describe, and if these structures are passed as return values or reference arguments, then all intervening layers of the software will have to know about those data structures. Then, when the internals of those data structures change, all the intervening modules will have to be recompiled. This paper presents a pattern called "Capsule" that provides a way for distant layers of software to communicate without creating unwanted dependencies between the interviening layers.