The completion of the human genome project has marked the official start of the post-genomic era. Due to limitations in DNA and RNA studies, the advent of proteomics, or large-scale analysis of proteins, is considered a crucial consequence and a chief player of post-genomic initiatives. An immediate goal of proteomic studies is the understanding of proteins including their expression, function, interaction, and structure with an endpoint of discovery of protein biomarkers. Such biomarkers can be used in detection, prognostication, and treatment of diseases. However, the challenge of studying complete sets of cellular proteins, or proteomes, is driving the development of newer technologies. In this review, a discussion of proteomic biotechnologies and their clinical applications is offered. The main techniques covered are the 2-dimensional polyacrylamide gel electrophoresis, mass spectrometry, surface-enhanced laser desorption ionization mass spectrometry, and protein microarrays. These tools have been successfully utilized in analyzing human and other biological samples in discovery of biomarkers. Recent advancement in proteomics has added and will continue to add valuable information to our knowledge-base of the human biological system.