Defects in semiconductors can be difficult to characterize, especially in complex semiconductors such as the chalcogenides. This talk presents several different and relatively unusual methods for their study along with examples of results. The talk will focus on semiconductors used for photovoltaic applications but the talk should illustrate methods that would be of use with any semiconductor material. Specifically the talk will address the use of admittance spectroscopy, nuclear magnetic resonance (NMR), scanning microwave impedance microscopy (SMIM), scanning tunneling spectroscopy (STS) and others to study defects in CdTe, CuInSe2 (CIGS), and Cu2ZnSnS4 (CZTS), and related compounds. Examples of results include the identification of two defects in the energy gap of CIGS by admittance spectroscopy, band edge fluctuations in CIGS by STS and their impact on the ability to obtain atomic resolution images, organized point defect structures in CZTS by NMR, and grain and grain boundary behaviors in CdTe by SMIM. Other examples will be included as time permits.