Water-emulsifiable polyisocyanate compositions admixed with at least one solvent of formula (1) (R1O)2C(R2)—X—R3 are formulated into aqueous emulsions which advantageously further comprise a compound, bearing a mobile hydrogen function, or a compound containing precursor functions capable of liberating hydroxyl functions, and are useful for producing coatings on a variety of substrates, e.g., made of cement, wood or leather in particular, and also for producing adhesives.