Project Summary For patients with end-stage renal disease, kidney transplantation is the best clinical treatment. While this procedure improves kidney function and survival in these patients, kidney transplantation is also associated with an increase in cardiometabolic disease, which includes glucose intolerance/insulin resistance that leads to development of diabetes mellitus, which may impact on the transplanted kidney. Weight and adipose gain following kidney transplantation has been implicated for these deleterious cardiometabolic effects, and potential impact on kidney function and kidney graft failure. The increase in weight/adiposity may be related to a combination of medications related to transplantation and/or positive energy balance resulting from an increase in energy intake without a sufficient compensatory increase in energy expenditure (e.g., increased physical activity). Interventions to address weight gain have focused on the prevention of positive energy balance (energy intake does not exceed energy expenditure). There is a scarcity of rigorous data available in the literature addressing dietary interventions and the effect on body weight following kidney transplantation. The existing literature of diet or diet plus physical activity has moderate to high risks of bias that limit the use for drawing conclusions on prevention of weight gain and related onset of impaired glucose metabolism. We propose a study of high scientific rigor to address this limitations in an effort to enhance the health of kidney transplant recipients. We propose this study to build on our intervention and clinical experience to conduct a 6- month pilot and feasibility study in patients who have received a kidney transplant. We will initially undertake efforts to refine our intervention components to confirm their applicability to this patient population. We will the recruit and randomize participants to Standard Care or a Lifestyle Intervention focus on weight gain prevention. The aims of this study are: 1) We will adapt our intervention approach to this patient population, 2) We will examine the feasibility of randomizing and retaining participants within our approach, 3) We will examine fidelity and compliance to the components of the intervention, 4) We will conduct safety monitoring to assess for adverse outcomes that are specific to kidney transplantation. Based on this pilot and feasibility clinical trial, and our “Go/No Go” criteria, we will finalize the study protocol, manual of procedures, and effect size estimates for a subsequent full-scale R01 application.