A brief summary of the observed infrared and other properties of interstellar dust is given. Chemical, physical and morphological criteria are discussed concerning the degree to which there are constraints relating comets to interstellar dust chemistry representative of the presolar nebula. Results of theoretical modelling of dust and gas evolution in dense clouds are used to compare with observed dust composition. Sources of the distribution of simple as well as complex molecules in the coma are related to what is presently known about the volatile ices in interstellar dust and to processes leading to evaporation of organic “refractory” grain mantle material represented by laboratory residues produced by photoprocessing of ices. The criterion of preservation of interstellar volatiles in comets leads to the further criterion that the ice in comets is amorphous. Criteria for relating interstellar dust volatiles to asteroids are discussed.