Development of renal fibrosis is the irreversible culmination of various renal diseases and independently predicts adverse outcomes. Currently renal fibrosis can only be diagnosed by performing a renal biopsy. The procedure is invasive and is limited by sampling bias. In recent years there has been a significant development in magnetic resonance imaging (MRI) based techniques. MRI can provide highly detailed anatomical images. Other MRI measures allow quantitative measurements of perfusion, oxygenation, tissue stiffness and diffusion of water molecules within tissue. The combination of several MRI techniques sensitive to different biophysical tissue properties in a single scan session is referred to as multiparametric MRI (mpMRI). Emerging evidence suggests that mpMRI could represent a method for indirect characterization of renal microstructure and extent of fibrosis. So far, studies performed in living kidney donors and recipients have been mostly cross-sectional. For mpMRI to transition to the clinical setting there is a need for validation of MRI-based measures with currently used reference methods for quantifying renal function and fibrosis. The aim of this longitudinal observational study in a cohort of living kidney donors, recipients and healthy controls is to investigate the utility of repeated mpMRI over a period of 2 years. MRI-based measures will be compared to current reference methods for quantifying renal function and fibrosis. The investigators hypothesize that there will be significant correlations between MRI-based measures, renal function determined by precise measurement of glomerular filtration rate and extent of fibrosis determined by renal biopsy. MRI-based measures are expected to be predictive of renal function decline and development of renal fibrosis. This study could provide valuable data that will be helpful in moving the field of renal mpMRI forward, with the goal of providing a novel and non-invasive method for the diagnosis of renal pathology.