The CRO industry is valued at $25-30 billion globally and is growing at a rate of 7-9% annually. Preclinical services make up 25% of spending while phases I-IV clinical trials account for 75%. Growth has been driven by increasing trial volumes, complexity, and the ability of CROs to perform services more cost efficiently. Top CROs now account for 50% of the market. Emerging trends include personalized medicine approaches and use of big data, virtual trials, and digital biomarkers. To remain competitive, large CROs need to innovate in these areas and develop new models to better serve smaller biotechs and pharmaceutical companies.