The Renaissance experiments in quantitative meter in English pose a long-standing puzzle: not only have their specific principles of composition proved elusive; so has any more general explanation of their ultimate failure. This article argues that the solution to the puzzle lies in interactions of quantity and stress in both the meter and the language. An analysis of the dactylic hexameter as based on moraic trochees explains why stress is more straightforwardly accommodated by some positions than others. Analyses of stress-induced ambiguities in English syllable quantity such as the resyllabification of intervocalic consonants in C[V acute]C[V times over] contexts explain apparent inconsistencies in scansion. When these complexities are taken into account, Sidney's compositions reveal themselves to be systematic and phonologically well founded; ambiguities are acknowledged and the meter is exploited to structure them. Ultimately, however, such ambiguities mean that quantity alone provides an inadequate basis for meter in English, because it underdetermines the metrical possibilities.