An integrated sedimentological, stratigraphical, structural and geochemical study has been used to establish the tectono-sedimentary evolution of the Pelagonian and Vardar (Axios) zone in N Greece. This is a key area for understanding the evolution of the Neotethyan ocean. The Pelagonian zone is interpreted as a rifted (Gondwana derived) continental fragment, whilst the Vardar zone formed a bordering Neotethyan ocean basin to the E. This study concentrated on the W part of the Vardar zone (Almopias subzone). A major aim of this thesis is to establish the evolution of sequences along the Pelagonian continent-Almopias ocean interface, from Permo-Triassic to Tertiary time. Rifting of the Almopias zone was probably initiated in the Permo-Triassic, resulting in ocean basin formation (WPB to MORB-type crust) by at least Upper Triassic (Vryssi Unit), and deposition of a clastic sequence in the Pelagonian zone followed by the establishment of a thick sequence of algal marbles during the Mid Triassic to ?Liassic (Pelagonian platform). Thus a clear W-E proximal to distal facies change from the Pelagonian zone to the Almopias zone can be recognised. Intraplatformal basins also developed within the Pelagonian zone at this time, whilst the Likostomo/Livadia-Klissochori-Rhizarion fragment possibly represented an isolated rifted fragment (Pelagonian derived) in the Almopias zone. By at least the L-M Jurassic a ocean basin existed in the Almopias zone. Its E limited was marked by subduction beneath the Paikon arc. During the M Jurassic the Pelagonian platform underwent dramatic subsidence associated with the transition to a foreland basin ahead of emplacing ophiolite nappes and parts of a subduction-accretion complex. Geochemical and stratigraphical data suggest a Pindos derivation. MORB, WPB and BSV volcanics are present. Complete subduction of the Almopias ocean also took place at this time by a combination of subduction beneath the Paikon arc and collision between the Paikon and Likostomo-Livadia fragments with the E margin of the Pelagonian zone. This was associated with transpressional (dextral) deformation and metamorphism of the E Pelagonian zone (Eohellenic event). A transgressive cover of Oxfordian-Kimmeridgian age throughout the Pelagonian and Vardar zones dates the age of ophiolite emplacement and Eohellenic deformation.