Use Calhoun and the HSDL to find previous NPS dissertations and theses in your area of interest. NPS theses can be searched by the usual author and title fields but you can also refine your search to locate theses of interest by Degree Award, and branch of service. To locate examples of high quality theses use the phrase "outstanding thesis."
The Homeland Security Digital Library (HSDL) inlcudes a focused collection of Homeland Security Related theses, dissertations and reports. CHDS Theses are available HERE.