Elucidating the mechanisms and rates of silicic continental crustal growth and preservation is essential to understanding the geochemical differentiation of Earth. The Ketilidian Orogen in South Greenland represents one segment of the Great Proterozoic Accretionary Orogen, which was a longlived external convergent margin stretching from Laurentia through Baltica and potentially beyond that partly encircled and contributed to the formation of the supercontinent Columbia (also known as Nuna). The Ketilidian Orogen represents a continental arc bordering Archean crust of the North Atlantic Craton. It is subdivided into the Central Domain, which is dominated by high-K, calc-alkaline gabbroic to I-type granites of the 1.85-1.80 Ga Julianehåb Igneous Complex (JIC), and the Southern Domain, which comprise fore-arc sediments that were metamorphosed to amphibolite and granulite facies at ca. 1.79-1.76 Ga and then intruded by rapakivi granitoids and related mafic units of the Ilua Suite (ca. 1.75-1.73 Ga). The balance between juvenile mantle-derived extraction, infracrustal reworking and crustal recycling needs to be evaluated in order to understand the growth of continental crust. The use of coupled in situ zircon U-Pb, Lu-Hf and O isotope analyses have grown widely popular as tool to address these questions since the beginning of the century. The approach have been applied in this project to assess the crustal controls involved in the evolution of the Ketilidian Orogen with main focus on the JIC and the Southern Domain. The first manuscript included in this thesis presents new zircon U-Pb geochronology from the west parts of the JIC, which expands the regional age coverage and provide new insights into the temporal evolution of the JIC. The age data suggest that the second growth stage at ca. 1.80 Ga was volumetrically major of flare-up magnitude and split as well as significantly expanded the arc. The second manuscript addresses the source from which the plutonic rocks of the JIC derived, through means of zircon Hf and O isotopes, whole rock Nd and Hf isotopes and major- and trace element geochemistry. The data implies varied influence of older crustal contaminants and negligible involvement of sedimentary material that interacted with water at low temperatures into the generally juvenile source. Therefore, the Ketilidan Orogen should no longer be referred to as solely juvenile, mantle-derived crustal growth. The third and last manuscript presents coupled zircon U-Pb-Hf-O isotope data among other on the metasedimentary- and Ilua Suite rocks within the Southern Domain to investigate their petrogenesis and provenance. The detrital zircons in the metasediments contain Hf compositions resembling compositions within JIC as well as an age spectrum that match JIC, but also have a smaller nevertheless significant population of older zircons not observed in the JIC. However, the metasediments have heavy O isotope signatures that are not consistent with the O isotope compositions in the zircons within JIC. This study suggests that the O isotope signatures in zircon were partially to fully reset during high-grade metamorphism due to oxygen diffusion, whilst the U-Pb and Hf isotopic systematics remained unperturbed. The zircon isotopic composition of the Ilua Suite mimic those of their host rock, thus magmatism was dominated by local crustal sources. Collectively, these manuscripts highlights the evolution of and connection between the arc and forearc that constitute the Ketilidian Orogen during the Paleoproterozoic. Furthermore, these studies provide good examples of the use of combined zircon U-Pb-Hf-O isotope analyses on plutonic- and metasedimentary rocks, where the latter gives important implication for interpretation of detrital zircon compositions in old, metamorphosed rocks.