Biologic pharmaceuticals are gaining in both market share and clinical utility compared with small molecule therapeutics. This market growth is, in part, reflective of a field of science entering its toddlerhood, where with increased maturity, both development timelines and costs of manufacturing for these complex molecules will decrease, further enhancing the profitability side of the equation. Although a firm understanding of the rules governing toxicity (especially antibody responses to therapeutic proteins) remains to be defined, it is clear that proteins are less prone to much of the idiosyncratic toxicity associated with small molecule drug candidates. Proteins are disadvantaged in that they are unlikely to find much use in targeting intercellular processes; however, they have clear strengths over small molecules in targeting protein-protein interactions and the specific targeting of surface features of particular cells (e.g., in oncology). As each aspect of protein pharmaceutical technology advances, it is clear that this will be the major area for growth in the industry over the next decade.