Articulatory proficiency of /r/ and /s/ sounds, voice quality and resonance, speech intelligibility, and intraoral sensation were examined prospectively before operation, and at four time points during a 1-year follow-up after microvascular transfer. Forty-one patients with a large oral or oropharyngeal carcinoma undergoing tumor resection and free-flap reconstruction usually combined with radiotherapy participated in the study. Articulation, voice, and resonance were investigated both live and from recorded speech samples by two trained linguistic examiners. The patients completed a self-rating of their speech intelligibility and were assessed for anterior intraoral surface sensation by means of 2-point moving discrimination. Misarticulations of /r/ and /s/ increased significantly after the therapy. Voice quality and resonance remained essentially normal. Speech intelligibility deteriorated significantly. Intraoral sensation decreased postoperatively but was not related to speech outcome. Sensate flaps did not prove to be superior in relation to speech tasks. A multidisciplinary approach is advocated in assessment of speech outcome after cancer surgery. Speech therapy is strongly recommended, even in the absence of a gross articulatory handicap.