Starting from January 2010, Enamine starts offering screening compounds via three separate libraries: Advanced, HTS and Historical collection. Advanced collection will always contain only novel and recently synthesized compounds, thus clients who persistently monitor additions to Enamine stock will spend less time and efforts to find new structural motifs. HTS collection will continue to be an indispensable source of compounds for various screening needs, providing unparalleled choice of diverse chemotypes. Historical collection will contain compounds representing scientific heritage of major regional research groups and institutions, particularly interesting for research programs in agro-chemistry and material science.