Two studies of adult aphasia, focusing on phonological disturbances, are presented. In the first study, subjects were 15 adults wit moderate aphasia and five age-matched controls. A variety of speech production and speech perception tests were administered, including tests of syllable discrimination, auditive word-picture matching, articulation, repetition of real words and non-words, naming, and picture description. Results of these tests are summarized and compared. In the second study, subjects were ten aphasic patients with a range of fluency and two controls. This research tested (1) the reliability of the clinical classification of aphasia into fluent and non-fluent types; and (2) the success of the two-stage view of speech production in predicting the nature of speaker errors. Two tests were used: one tested listener judgment of articulatory fluency, and an acoustic analysis of format frequencies and duration of eight Finnish vowel phonemes in the first (stressed) syllable. Results of these tests are also discussed. A 125-item bibliography is included. Appended materials include the tests, notes on Finnish phonology, materials related to the tests, and summarized test results. (MSE)