Stable isotope labeling with amino acids in cell culture (SILAC) is considered the most accurate method for proteome quantification by mass spectrometry. As it relies on active protein translation, it was traditionally limited to cells in culture and was not applicable to tissues. We have previously developed the super-SILAC mix, which is a mixture of several cell lines that serves as an internal spike-in standard for the study of human tumor tissue. The super-SILAC mix greatly improves the quantification accuracy while lowering error rates, and it is a simple, economic, and robust technique. Here we describe the design and application of super-SILAC to a broad range of biological systems, for basic biological research as well as clinical one.