The area of study is compounding in modern English poetry. The works form which examples of compounding are taken are poems by contemporary poets such as Ted Hughes, Peter Redgrove and others. That many of the compounds found here are not generated by the grammar is shown by giving an account of the grammar of standard language compounding in English. This is done in terms of a system of interacting principles, along the lines of recent generative grammatical studies of word-formation such as Lieber (1980), Selkirk (1981), Toman (1983). The exact way in which the poetic compounds in question are deviant is established on the basis of this grammar. The deviance is shown to be systematic in nature by presenting a small number of poetic principles, such as metaphor or iconicity, whose interaction with the principles of SL grammar accounts for the deviant compounds in question.