The presented monograph introduces the processes of vocabulary and grammar (primarily morphology) acquisition in one Czech child over a long time span. The research is based solely on the analysis of authentic material (the corpus of transcriptions of audio recordings and the parental diary), and it covers the period from the onset of speech until three and half years of age in the target child's development. The longitudinal study is oriented toward the acquisition of a lexicon and the acquisition of grammatical categories of inflectional parts of speech, namely, nouns, adjectives, pronouns and verbs. The analysis is largely building on the concepts of premorphology, protomorphology and modularised morphology. The results support the assertion that both grammatical and pragmatic competences are interrelated and that one limits the other.