Developing photovoltaic (PV) powerplants close to airports, major roads and residential areas could pose potential challenges related to glint and glare. Glint and glare impact assessment (GGIA) has subsequently become an important tool for assessing potential impacts. This study analyses of a range of GGIAs, standards, and guidance to recognise and make recommendations for best practice. Twenty GGIAs are conducted by various consultants from diverse countries, and seven standards and guidance are critically reviewed with respect to practice for: methods; impact significance determination; mitigation; and stakeholder engagement. Key recommendations for best practice are made, albeit recognising that they reflect the best of existing practice which is not necessarily the best practice that might be aspired to. This study serves as a first step toward improving GGIA practice, with the ultimate objective of supporting the safe and sustainable development of solar PV projects.