1. A method for use with a speech-enabled application, the method comprising: receiving input from the speech-enabled application comprising a plurality of text strings; generating, using at least one computer system, speech synthesis output corresponding to the plurality of text strings, the speech synthesis output identifying a plurality of audio recordings to render the plurality of text strings as speech, at least one of the plurality of audio recordings being selected to render at least one portion of at least one of the plurality of text strings as speech carrying contrastive stress, to contrast with at least one rendering of at least one other of the plurality of text strings; and providing the speech synthesis output for the speech-enabled application.