INTRODUCTION: Parkinson's disease (PD) is a growing neurological challenge. The Sit-to-Stand (STS) transition is a key proxy for functional independence and fall risk. While sensor technology offers objective STS assessment, the methodological landscape is highly heterogeneous, lacking standardized protocols. This scoping review systematically maps the literature on the technological assessment of the STS transition in PD, focusing on sensors, tasks, settings, and variables. Additionally, the review details device accessibility and ecological validity in home-based settings, as these are two important elements for large-scale application and implementation in standardised protocols for both clinical assessment and real-world monitoring. METHODS: A scoping review following Joanna Briggs Institute and PRISMA-ScR guidelines. Five major databases (PubMed, Embase, CINAHL, Scopus, Web of Science) and citation tracking were used to identify studies from 2015 to 2025. Eligibility criteria included studies with PD patients of any stage undergoing instrumental STS transition assessment. We mapped data according to sensors, tasks, settings, and variables. We performed specific subanalyses on Inertial Measurement Units (IMUs)-distinguishing research-grade 'kinematic' sensors from consumer 'Mobile' devices-and assessed ecological validity (unsupervised vs. supervised) in home-based settings. RESULTS: From 7,368 records, 77 studies were included. Four dominant trends emerged: (1) Technology: IMUs were used in 87% of the studies. (2) Protocol: the Timed-Up-and-Go (TUG) test (60%) was more prevalent than pure STS tasks (22%), (3) Setting: Most assessments occurred in outpatient settings (79%), followed by home-based settings (25%). (4) Functional variables: despite technological sophistication, 'duration' remained the primary variable followed by linear acceleration and angular velocity. Moreover in the home setting, while 74% of studies achieved high ecological validity (unsupervised), a "scalability gap" emerged: 63% still utilized complex research-grade IMUs. CONCLUSION: Instrumental STS transition assessment in PD is a rapidly expanding field. It is dominated by IMU sensors, but fragmented by protocol heterogeneity and a critical "scalability gap" in home monitoring. Complex variables still require non-scalable sensors, while scalable mobile devices have not yet been validated for advanced metrics. Future work must develop robust algorithms for mobile devices and validate metrics to standardise protocols for clinical assessment versus ecological monitoring.