This paper investigates a type of grammatical ill-formedness in English which is traceable to the repetition, under certain specified conditions, of present participles, e.g. the verb "continue" cannot occur with participles if it is in the present progressive. The solution to generalizing about ill-formedness of this type is by means of a derivational constraint which is formulated in such a way as to link certain features of remote structure to certain features of surface structure. The violation is not stated in terms of a restriction on transformations but rather as a static filter on the output of the syntactic component. This paper refines and formally states the requisite derivational constraint so that it is not too powerful. The author examines the consequences for linguistic theor y of postulating such a derivational constraint. The argument for using such a constraint, details on its development, and references are presented. (Author/VM)