Background: Primary schools need well informed and highly motivated teachers to meet the evolving demands of the education system. Professional development is essential to equip primary school teachers to change practice to meet these challenges (Guskey, 2003; Villegas-Reimers, 2003). The purpose of this study was to describe, analyse and understand teachers’ and children’s experiences of a contextualised, whole school professional development programme (PDP) in primary physical education. Research Design: A case study methodology was employed informed by social constructivist theory. The study was broken into four phases. Phase one described the case and provided an in-depth professional development needs analysis of the teachers. Phase two resulted in the development of a school specific, contextualised PDP on Outdoor and Adventure Activities. This programme was based on features of effective professional development (e.g. Armour & Duncombe, 2004; Desimone, 2009; Garet et al, 2001; Guskey, 2002; 2003; O’ Sullivan & Deglau, 2006; Wayne et al., 2008) and was informed by professional development instructional models (Caffarella, 2002; Collins et al, 1991; Joyce & Showers, 1988; Maldonado, 2002). Phase three was the implementation of stage 1 of the PDP, this phase included a process evaluation. Phase four involved stage 2 of the PDP, where the teachers taught the O&AA unit with less intense support. It included both process and impact evaluation of the PDP. Teachers were supported for one hour during their timetabled physical education lesson each week for six weeks during stage 1 and again at stage 2. Further support was provided when requested by teachers outside of these times. Methods: The research methods selected were primarily qualitative due to the exploratory nature of the study however quantitative methods were used in order to provide a more generalist picture when relevant. This mixed methods approach allowed for i) an in-depth understanding of the research environment and ii) a full analysis of how the PDP was impacting primarily on the teachers, but also on the children. The methods of data collection employed were specific to the research questions in each phase and included questionnaires, physical health and fitness measurements, focus-group discussions, semi-structured interviews, field notes, lesson evaluations and systematic observations of teachers and children. Analysis: All quantitative data were analysed using SPSS for Windows, version 14.0. Data were presented descriptively as means, standard deviations and percentages and where appropriate gender- and age-specific means and standard deviations were calculated. The Pearson, chi-square statistics with standard residuals was used to investigate any categorical relationships in the data. Paired sample t-tests, or Mann-Whitney U tests were conducted to compare differences. All qualitative data were coded and categorised using constant comparative technique, facilitating the identification of similarities and differences, the grouping of data into categories and the development of propositional statements. Findings: A single, suburban mixed gender primary school [Principal, teachers: N=28 (year 1), N=27 (year 2) and pupils: N=780 (year 1), N=800 (year 2)] participated in the study. Prior to the PDP the teachers taught a narrow programme of physical education using direct teaching styles. Teachers reported lacking content knowledge and confidence in teaching O&AA (pedagogical content knowledge). Children, prior to the PDP, enjoyed physical education and expected lessons to include moderate to vigorous levels of physical activity. They met normative standards for physical fitness for their age and gender. However, they described their physical education experiences as predominantly ‘games’ and recreational rather than educational. Both the teachers and the children had a confused understanding of physical education with discourses focussing on health and physical activity. Following implementation of the PDP the findings indicated that for the PDP to be effective and change to occur key features were necessary (described using the developed propositional statements). These were: a) The teachers reported that the provision of resources played a strong role in the adoption of the PDP; b) The support provided by an external expert through modelling lessons, explaining activities and providing feedback impacted positively on teachers’ teaching; c) The support allowed teachers to build on their content knowledge and they gained confidence to use already developed classroom pedagogical strategies in the physical education context; d) Organisational changes within the school, such as timetabling and access to equipment, were necessary for the PDP to be successful: e) The PDP impacted positively on children’s perceived learning and engagement in physical education lessons; f) Both teachers and children began to re-conceptualise physical education, from a games orientated, recreationally focused subject towards an understanding of physical education as a subject where teaching and learning happened; g) Collegiality and collaboration amongst teachers in physical education, and in other subjects, was an outcome of the PDP and was an important change strategy. Conclusion: This research confirms the importance of resource provision, contextualised and individualised support to develop teachers’ content and pedagogical content knowledge in the design of a PDP. It also provides evidence of the teachers themselves being an important resource and the need for future professional development to incorporate opportunities to facilitate communication and collaboration and formalise communities of practice. Teacher change is underpinned by the features of the PDP and the research indicates that change is multi-directional. Although the literature highlights the necessity to focus on the learning outcomes of the child in designing PDPs, it is imperative that we do not ignore the learning outcomes of teachers. If there is no teacher learning, this could potentially limit children’s learning.