This thesis investigates the first language acquisition (L1A) of pronominal object clitics in Cypriot Greek (CG) by typically developing (TD) children, focusing on an exceptional form of non–adult–like clitic placement attested in early data. The aim of the present study is twofold. On the one hand, it aims to sketch the developmental stages in the course of L1A of CG in relation to other clitic languages. On the other, it investigates whether and to what extent syntactic (Agouraki 2001, Terzi 1999a, 1999b), prosodic (Condoravdi and Kiparsky 2001) and interface approaches (Mavrogiorgos 2012, Revithiadou 2006) can account for early clitic production. Research on L1A of clitic pronouns has demonstrated both clitic realisation and omission in child languages. However, no instances of clitic misplacement have been reported for early European languages, with the interesting exceptions of CG (Petinou & Terzi 2002) and European Portuguese (Lobo & Costa 2012). The present thesis examines the L1A of CG in the age range 2−4 on the basis of spontaneous and experimental data, cross−sectional as well as longitudinal, with a focus on clitic placement. Spontaneous speech data were collected from 8 children, and one of the children was also followed longitudinally for a period of 6 months. An elicited production task performed by 50 children was used to generate 3rd person singular accusative object clitics. The results of the study indicate that, for CG: (i) clitic placement in enclisis environments is adult–like from the onset in structures involving single clitics and clitic clusters, as well as in Clitic Doubling and Clitic Left Dislocation; (ii) clitic misplacement is attested in proclisis contexts in a subset of children aged 2;6 to 3;0; (iii) clitic misplacement does not correlate with early non–finite forms; (iv) occasional realisation of two copies of the clitic is attested in some children aged 2;6 to 3;0; (v) by age 3;6, TD children manifest adult–like clitic placement. These findings raise issues regarding the acquisition of clitics in different classes of languages (Tobler–Mussafia, finiteness–sensitive languages, languages exhibiting second position restrictions), as well as the role of syntax, prosody and the syntax–phonology interface in clitic L1A. The current study suggests that only Tobler–Mussafia languages display clitic misplacement, as attested in the L1A of CG. Clitic misplacement in CG is interpreted within an interface account in line with Revithiadou (2006) and, following the spirit of Bošković (2000), it is assumed that the placement requirement imposed on CG clitics “can be captured in its entirety through a filtering effect of the phonology on the syntax” (2000:105). Clitic placement in CG is an interface phenomenon: the syntax provides two copies of clitic pronouns (Franks 1998) and the syntactic outcome is filtered through a phonology–controlled procedure.