The choice of the emitting material for the photocathode in the photoinjector is driven by many boundary conditions and goals. During this workshop we want to discuss these goals, boundary conditions and the various options for present and new emitting materials. Furthermore we want to shed light on instrumental techniques for the preparation, treatment and characterization of the emitting materials. The Helmholtz Initiative for Accelerator Research & Development (ARD) was established to strengthen development in accelerator physics and technology and to ensure international competitiveness. In this framework, accelerator scientists push the limits of today’s technology in a research network of six Helmholtz centers (Deutsches Elektronen-Synchrotron (DESY) in Hamburg and Zeuthen, Helmholtz Zentrum Dresden-Rossendorf (HZDR), Forschungszentrum Jülich (FZJ), Helmholtz Zentrum for Heavy Ion Research GSI in Darmstadt, Karlsruhe Insitute for Technology (KIT), and Helmholtz Zentrum Berlin for Materials and Energy (HZB) ), two Helmholtz institutes, eleven universities, two Max-Planck institutes, and the Max-Born institute.