Successful proteome analysis depends on standardized, reliable, and convenient sample preparation. EMD Biosciences, through its Calbiochem® and Novagen® brands, offers a comprehensive selection of sample preparation tools for three main areas of protein research: expression proteomics, functional proteomics, and structural proteomics. Most often, expression proteomics includes the comparative analysis of proteins expressed in cells under varying conditions, whether in response to a disease, chemical compound, or therapeutic drug. These differentially expressed proteins can serve as potential drug targets or as biological markers for disease detection. The ProteoExtract® and ProteoEnrich™ kits cover the different steps in sample preparation, from protein extraction and abundant protein removal to concentration of protein mixtures, removal of interfering substances, digestion of proteins, selective capturing of phosphorylated peptides, and selective enrichment for specific protein classes. All kits are compatible with each other. Many of our kits are designed to produce samples that can be used directly in applications such as activity assays, protein microarrays, SDS-PAGE, immunoblotting, ELISA, two-dimensional gel electrophoresis (2DGE), mass spectrometry (MS; including MS/MS, LC-MS, MALDI-MS, SELDI-MS, and ESI-MS), and others.Structural protein analysis requires a considerable amount of purified protein (20–30 mg on average) and, therefore, these analyses often begin with recombinant protein expression. When purifying proteins for functional or structural proteomics studies, the first step is to disrupt the cells or tissue sample and extract the relevant protein fraction. This step is critical because processing methods that require harsh mechanical, chemical, or enzymatic treatments can directly affect target protein integrity and activity, or otherwise expose proteins to degradative conditions. Our families of protein extraction reagents (BugBuster®, CytoBuster™, NucBuster™, YeastBuster™, PopCulture®, and Insect PopCulture products) are innovative combinations of detergents and other ingredients that enable gentle, efficient, nonmechanical extraction of soluble proteins from bacteria, yeast, plant, mammalian, and insect cells. The reagents are compatible with high-throughput recombinant protein purification and solubility screening.