The formation of imperatives (IMP) in Danish has for centuries been a challenge, both to native speaker-hearers and for language policy, and it has been discussed in grammars since the 17th century. The best way to state the principle of IMP-formation in Danish is: IMP is formed by subtracting a final e-schwa (/ə/) from INF; if INF does not end in e-schwa (/ə/), IMP = INF. In many cases, the IMP thus constructed is not, or does not end in, a well-formed syllable, e.g. hækl! [hεɡ̊ l] ‘crochet!’, saml! [sɑmˀl] ‘collect!’. Such forms do not obey sonority or strength hierarchies, and there are different ways to cope with that challenge. Danish IMP-formation represents several types of conflicts with respect to the morphology/phonology interface, and it illustrates several descriptive and theoretical problems in accounting for them: both between morphology and phonotactics (sections 1 and 5), and between morphology and prosody (sections 6 on vowel quantity and section 7 on the stød, a laryngeal syllable rhyme prosody with a complex grammatical distribution). This paper proposes a coherent account, based upon Basbøll’s Sonority Syllable Model — a non-circular cross-linguistic model of sonority or strength — (section 4), and his Non-Stød Model. The latter model involves a general procedure for the integration of suffixes in word structure (section 8) and its application to modern Danish (section 9). Throughout the paper, methodological and theoretical problems are in focus, but finally, the need for empirical investigations of Danish IMP-formation is emphasized, concerning the question how Danish speaker-listeners, and also foreign learners of Danish, cope with the challenging IMP-forms.