A report from TNTP (formerly The New Teacher Project) raised eyebrows recently when it concluded that much of the professional development teachers receive does little to improve teaching quality. The report, provocatively titled "The Mirage: Confronting the Hard Truth About Our Quest for Professional Development," examined the professional growth of some 10,000 teachers in three large urban districts and a charter school management organization, hoping to discover what distinguished the experiences and dispositions of the "improvers"--the roughly 30 percent who demonstrated year-over-year growth on performance evaluations--from those of the "non-improvers." Notwithstanding the boldness of making such a broad-brush statement after examining just four school systems, it's true that research supporting the effectiveness of professional development can seem like a vast desert where even seemingly effective practices fade as educators get closer to them. This article examines whether or not peer coaching and teacher collaboration is the oasis educators have been searching for in the otherwise bleak desert of professional development.