The purpose of real time clinical gait analysis (RTCGA) is to aid in diagnosis of musculoskeletal (MSK) conditions, determine treatment goals and evaluate treatment outcomes. Clinicians are recommended to conduct RTCGA as part of a lower limb MSK non-neurological adult patient assessment. The timely and accurate use of such a diagnostic method, with the smallest possibility of a missed diagnosis or misdiagnosis, is crucial in the treatment of any disease or disorder. Despite this, there remains little MSK RTCGA evidence to support the methods by which to do so. This PhD reflects a programme of work which was undertaken to develop a best practice RTCGA approach for adult non-neurological lower limb MSK injury. The research aim was to establish a best practice approach for RTCGA to be used as part of a clinical MSK assessment in the treatment of non-neurological lower limb symptoms in adults. This doctoral thesis programme of work employed a mixed methods approach, involving a series of deductive quantitative investigations followed by inductive qualitative investigation. Deductive quantitative investigation involved scoping of the RTCGA best practice approach via narrative literature review, a patient and public involvement and engagement (PPIE) exercise and preclinical testing. A systematic review was conducted to robustly establish available MSK RTCGA literature. Inductive, qualitative investigation involved exploration of MSK podiatrists’ views and experiences of RTCGA for an exemplar condition, posterior tibial tendon dysfunction (PTTD), using thematic analysis of semi-structured interviews. Findings supplied the foundation by which preliminary clinical recommendations for a MSK RTCGA best practice approach were created. A preliminary objective RTCGA instrument was created. Scenario testing for face validity demonstrated this preliminary RTCGA instrument would not detect kinematic changes following intervention, and an additional immediate intervention RTCGA instrument was developed. The resultant preliminary RTCGA instrument, which was then subject to preclinical testing, consisted of 2 sections, the RTCGA instrument score and the RTCGA immediate intervention score. Preclinical investigations demonstrated difficulties in the ability to test the preliminary RTCGA instrument for both reliability and validity. Literature review and searches from narrative, systematic and PPIE investigations found a lack of high-level evidence and guidance for the use of RTCGA and the development of RTCGA best practice approaches. In total, 6 substantial problems were encountered associated with the creation of an objective quantifiable instrument as a RTCGA best practice approach. These were a lack of existing RTCGA knowledge; developer bias; the necessity to include shod gait assessment; a lack of normative kinematic data; the length and complexity of the preliminary RTCGA instrument and an inability to transiently alter kinematics and obtain valid data for testing. These issues deemed the continued development of an objective quantifiable RTCGA instrument to be counterproductive. To understand the conundrum that an objective quantifiable RTCGA was not feasible yet is an approach suggested for use by clinicians (notably podiatrists) as an embedded component of their practice, the exploration of MSK clinician views and experiences of RTCGA was sought prior to attempting any further development. The resultant exploratory qualitative investigation confirmed that use of RTCGA was valued by MSK podiatrists, but that no consistent systematic approach for RTCGA was available. Based upon these findings, a set of 4 core recommendations are proposed as a preliminary best practice RTCGA approach when assessing and treating adult PTTD (the GAIT assessment). These are: Get a diagnosis (recommendation 1). RTCGA should be conducted after a provisional clinical PTTD diagnosis has been proposed. Assess walking (recommendation 2). RTCGA should be used to aid in clinical diagnosis of adult patients with PTTD. Assessment should include a) essential kinematic observations, and b) dynamic presentation of pain. Intervene and assess (recommendation 3). RTCGA should be performed after a clinical intervention, such as the fitting of foot orthoses or footwear, to observe any kinematic changes. If fitting foot orthoses, it should also be used to assess for patient perceived comfort. Teach using clinical experience (recommendation 4). RTCGA education should be addressed through an experiential approach, such as small group practical teaching and clinical mentoring. The research undertaken in this doctoral thesis programme of work is the first to apply development frameworks and methods in the attempt to establish a mechanism to record gait and gait changes within a MSK clinical setting, without the aid of computerised or video recording technology. A preliminary RTCGA best practice approach has been produced that supplies guidance for MSK podiatrists, in the form of the GAIT assessment, to aid in the clinical treatment and assessment of PTTD. However, the pathway to achieving a robust clinical practice guideline requires more work. The lack of objective kinematic data for this field was a significant barrier to investigating and improving reliability and validity of RTCGA observations. RTCGA, as an aid in the diagnosis and treatment of MSK injury, is arguably a high-level skill associated with professional specialisation. It follows, therefore, that such a skill would be supported by objectivity and standardisation of practice, yet the lack of normative data for RTCGA continues to act as a barrier to this. A new approach in which RTCGA is focussed on the patient symptoms and evidence based observation is proposed.