Many people with an intellectual and developmental disability (IDD) are biologically, socially, and economically/politically vulnerable to developing SARS-COV-2 (COVID-19) compared to the general population. Most governments have developed public-health policies and strategies to address the challenges that COVID-19 has presented. These policies and strategies have been based upon the general population and in fact could be detrimental to the health and well-being of people with IDD. This paper provides a review of the key learning points emerging from the COVID-19 literature, together with guidance for the provision of services and government interventions for people with an IDD for future pandemics. Using guidance from the Joanna Briggs Institute, a scoping review was used to explore the current literature (scientific and grey) on IDD and COVID-19. Three core themes emerged from the review. Prevention/protection: User-friendly accurate accessible information, handwashing and social distancing, Personal Protective Equipment, shielding, track and trace, testing, vaccine compliance/hesitancy, and training. Mitigation: Making reasonable adjustments both to where people live, and to community healthcare/clinical practice; and the use of technology as a pandemic-response strategy. Treatment/Management: Access to acute hospitals and lifesaving equipment, using a suitable clinical fatality assessment instrument, stopping Do Not Resuscitate notices, individualised care plans and hospital passports, family/paid carers to support people in hospitals; and use of telehealth in clinical care. This is the first international scoping review that provides a narrative synthesis of emerging themes related to the COVID-19 pandemic and people with an IDD. This paper highlights themes related to preventing, mitigating, and treating/managing the care of this population during the COVID-19 pandemic, which can inform future public-health policies. This paper also exposes the negative impacts of public-health interventions in both High-Income Countries and Low-Middle Income Countries for this population including lapses in upholding human rights. These data provide a basis for learning from the COVID-19 pandemic in planning for future pandemics.