Abstract: A combination of two anionic surfactants, one of which is an alkyl sulfate surfactant, such as sodium dodecyl sulfate, and the other of which is an N-acyl sarcosinate surfactant, such as sodium lauroyl sarcosinate, is used as a coating aid in aqueous coating compositions comprising a hydrophilic colloid. The combination of surfactants provides a coating composition which combines the advantage of good wetting or spreading characteristics with the advantage of excellent ability to avoid repellency defects. Such coating compositions are especially useful in the coating of gelatin silver halide emulsion layers or other hydrophilic colloid layers in photographic materials.