In this thesis I seek to establish an understanding of Loving Kindness Meditation (LKM), and to identify and evaluate the effects on wellbeing, that are claimed by practitioners and previous research. The context in which the thesis sits is the current focus on finding ways to improve wellbeing in the general public, to which LKM has the potential to contribute, given its unique focus on affect and connectedness, and their associated links with wellbeing. A mixed methods design was developed following a review of the limited current literature base. The review revealed discrepancies in how LKM was being employed. This included whether LKM was studied alone or in conjunction with other practices, the duration of exposure to LKM, and which aspects of the practice that were focused on during the practice. These differences may account for the variation in efficacy and the range of outcomes observed across the literature bases. As such, a programme exploring the impact of LKM on wellbeing, to test and affirm this assumption from theory and previous research findings, that employed a form of LKM that was reflective of realistic, everyday practice, was seen as useful. Two qualitative based studies were therefore used to establish an understanding of the practice, with practitioners who had a range of experience with LKM. The first study looked to clarify what the main aspects of the practice are, by interviewing very experienced LKM practitioners. Three themes emerged which spanned all aspects of the practice. Combined, these indicated that there was variation in how the practice is engaged with across the sample, with key components of the practice such as it being viewed more as a way of being, and elements such as connectedness and wholeness emerging as core underlying factors of the practice. The second study built on this, by expanding the sample to see whether the perception and understanding of the practice established from study one was consistent, or whether it was a viewpoint held by practitioners with extensive practice. To maintain depth of understanding, while identifying patterns of similar views, Q methodology was employed to sample a wide range of LKM practitioners. The resulting analysis indicated that there were consistent views held by the whole sample, evidenced by the placement of a few statements regarding the importance of the practice as a whole, as well as the self and enemies in the same area of the grid by all participants. This served to confirm, as well as add to, the key factors of the practice that had been observed in study one. The outcomes from the first two studies therefore fed into the design of the second two, which were more quantitative in design, and explored the impact of LKM in settings that were high in ecological validity; one online and one face to face. The third study made use of an existing programme, to explore the effects of the practice, as much of the previous literature focuses on interventions and programmes developed for purpose. The findings showed increases in wellbeing related measures, with exploratory analyses suggesting that self-compassion may be a key variable in linking LKM to improvements in wellbeing. The fourth study built on the findings from each of the previous studies, and explored the effects of an LKM programme developed to be in line with how existing practitioners engage with LKM. Additionally, to explore whether the focus of LKM resulted in different changes to other practices, a Mindfulness group was included as an active control. Findings suggested that LKM could impact positively on wellbeing related measures, with a measure of connectedness differing between the LKM and MM group in terms of magnitude of change. This indicated that connectedness is a core part of the LKM practice, compared to Mindfulness. Combined, the four studies complement one another in presenting a holistic understanding of LKM practice; how it can be understood, how it is practised, as well as what impacts the practice has. The thesis concludes by presenting the core components of the practice, but emphasises that connectedness is key. This was the factor that differentiates it from other practices such as mindfulness, the connection with the self and others may be one of the underlying mechanisms for how LKM results in positive change in the practitioner, and was a concept that was raised in every study in the thesis. In addition to this, the conclusions also suggest that given this core component of the practice, and the positive findings from the two studies that tested the impact of LKM, that the practice could be encouraged as a way of maintaining and improving wellbeing in the general public.