Chronic Kidney Disease (CKD) is common and often has a major impact on the health of those affected. In this thesis I have focused on areas of uncertainty that may have major implications for patient care. Firstly, I assessed the determinants of increased mortality in a multi-ethnic primary care population. Secondly, I investigated the differential progression of CKD between ethnicities. Thirdly, I assessed if tryptase, as a marker of mast cell activation, could be used to stratify risk in CKD. Finally, I investigated the impact of CKD on health related quality of life (HRQL) and the association between HRQL and clinical end-points. I found that: (i) comorbidity has a profound impact at a population level on survival in CKD; (ii) albuminuria is the principle modifiable risk factor for progression to end-stage renal disease (ESRD) in people of South Asian ethnicity; (iii) serum tryptase is an independent prognostic factor for ESRD in patients with CKD receiving treatment with an ACEi or ARB; and (iv) Low HRQL is common in CKD and reduced HRQL is associated with a higher risk for death. The findings from this thesis contribute to the understanding of CKD in ethnically diverse, high-risk populations and form the basis for further studies.