A comparative analysis of the organization of sponges has been carried out to clarify problems of their coloniality, individuality, and modularity. The morphological, physiological, morphogenetic, and immunological aspects of the problem have been analyzed. The followers of the hypothesis of colonial organization of sponges interpret the process of "new zooid" formation as an "incomplete asexual reproduction." A comparative analysis of morphogeneses in sponges during growth processes and asexual reproduction has clearly shown them to be different. A rearrangement (remodeling) of structures accompanied by disorganization and reorganization of tissues in neighboring elements of aquiferous system is the basis of growth. Migration of polypotent and secretory cells into the core of bud development is the major mechanism of budding. The formation of new aquiferous units (aquiferous modules) does not represent an "incomplete asexual reproduction." Thus, the terms "colony" and "zooid" cannot be applied to the sponges. A morphologically separate sponge, irrespective of its level of organization (ascon, sycon, or leucon) and the number of oscula (aquiferous modules) should be considered as an individual.