This study investigated development of speech sounds and syllable structure of words in 18 Zulu-speaking children between the ages of 3.0 and 6.2. A 100-word spontaneous conversational sample was elicited from each subject. All samples were transcribed phonetically by a stringent transcription procedure. The UNIBET was used to code the transcription into computer recognisablesymbols. The Phonetic Calculator Program (PCP) analysed the samples in terms of speech sound inventory, syllable structure of words and the frequency of occurrence of speech sounds and syllable structures. The data were processed to allow for the comparison of the findings at three age levels, namely 3.0-4.0 (Group 1), 4.1-5.1 (Group 2) and 5.2-6.2 (Group 3). There was developmental progression, but much speech and syllable structure development seems to occur before the age of 3.0. However, the speech sound inventory and syllable structure inventory were incomplete by the age of 6.2. The nasals, plosives, approximants and fricatives were found to develop earlier than the affricates, clicks and prenasalised consonant sounds. The shorter syllable strings were found to develop earlier than the longer syllable strings. The phonetically more complex sounds and syllable structures were produced more frequently by the older subjects, demonstrating developmental progression. The findings have important clinical implications for the speech-language therapist.