Knowledge Intensive Business Services (KIBS) are intermediary firms specialized in knowledge screening, assessment, evaluation, and trading services in the form of consultancy. Their emergence fits a wider trajectory in the development of modern knowledge economies whereby increasing sectoral specialisation requires the expansion of activities which facilitate cross-sectoral relations. In spite of continued expansion and diversification scholarly work still portrays KIBS as a homogeneous group of activities. This paper uses official data on occupational information in the United States in search of variety across KIBS sectors, and points specifically at differences in the occupational structures and skill requirements.