A common characteristic of subject-predicate agreement errors (usually termed attraction errors) in complex noun phrases is an asymmetrical pattern of error distribution, depending on the inflectional state of the nouns comprising the complex noun phrase. That is, attraction is most likely to occur when the head noun is the morphologically unmarked form and the local noun is a marked form. In the present study we investigated whether there is an asymmetrical pattern of distribution of agreement errors occurring in the course of producing subject-predicate gender (Experiment 1) and number (Experiment 2) agreement in Hebrew, using the sentence-completion task for complex noun phrases. In Hebrew, masculine forms are usually morphologically unmarked, whereas feminine forms are morphologically marked. Similarly, there are specific suffixes for marking plurality. Despite the apparent structural resemblance between number and gender marking in Hebrew, linguists suggest that whereas number involves inflectional processes, singular masculine as well as feminine nominal inanimate forms in Hebrew contain a complex derivational structure without inflectional suffixes. The results revealed that whereas producing gender agreement exhibited a symmetrical pattern of distribution of errors, the frequency of number attraction revealed an asymmetrical pattern, in which attraction was observed only when a singular unmarked head noun was followed by a morphologically marked plural form. The results are discussed in connection with the distinction between inflectional and derivational structures and their relevance to the process of computing agreement in the marking and morphing model (Eberhard, Cutting, & Bock, 2005). (Contains 5 tables and 2 footnotes.)