The synthesis of new water-soluble photoinitiators (PIs) based on hydroxyalkylphenones, benzophenones, and thioxanthones with carbohydrate residues such as glucose, cellobiose, and 1-amino-1-deoxy-D-glucitol (glucamine) is described. In addition, selected initiators were reacted with methacryloyl chloride to obtain copolymerizable initiators with improved migration stability. Results from photo differential scanning calorimetry and gel-content measurements in commercially available water-thinnable and emulsion-type resins as well as 2-hydroxyethyl acrylate are included. Glucose-modified PIS gave the best results with respect to compatibility with the resin, reactivity, and gel content.