This paper focuses on aspects of early lexical acquisition in German. There have been conflicting results in the literature concerning both the pattern of vocabulary growth and the composition of the early lexicon. Our study describes the development of various categories of words and questions the preponderance of nouns in spontaneous speech. 32 children were studied longitudinally through recordings made at age 1;1, 1;3, 1;9 and 3;0. The following properties of the data were investigated: vocabulary size in relation to age, frequency of word use, and distribution of word categories. The results show that use of both types and tokens increases with time. A trend analysis indicates an exponential increase in vocabulary production in the second year, followed by a further expansion. This vocabulary spurt-like pattern can be observed in the use of word types and tokens. The findings in regard to vocabulary composition illustrate the dynamics present in the development of word categories. In the beginning, children use mostly relational words, personal-social words and some onomatopoeic terms. These categories are gradually complemented with nouns, verbs, function words and other words so that we see a balanced lexicon by 3;0. Trend analyses clarify characteristic developmental patterns in regard to certain word categories. Our spontaneous speech data does not support a strong noun-bias hypothesis.