Research and development on engineered gene drives (EGDs) has expanded rapidly over the past decade, driven in part by the advent of CRISPR-Cas9 genome editing technologies. Much of this work has focused on insects, including plant pests, agricultural disease vectors, and species that transmit pathogens affecting humans, animals, and plants. As technological advances accelerate, so does the recognition of the need for a careful and forward-looking evaluation of their potential impacts. Gene drive modified organisms, including insects, present characteristics that differ substantially from previously assessed genetically modified organisms (GMOs), prompting growing calls for thoughtful and robust environmental risk assessment (ERA) frameworks tailored to these novel technologies. In earlier work, the GMO Panel of the European Food Safety Authority (EFSA) identified several information gaps that would need to be addressed to provide an adequate foundation for possible future risk assessment guidance. This report brings together and synthesises key elements to help close those gaps, including: an overview of the molecular mechanisms currently being explored for gene drive modified insects (GDMIs); potential use cases relevant to the European Union and its Outermost Territories; considerations for selecting a broader set of comparators for ERA; the role of computational modelling and ecological dynamics in shaping ERA for GDMIs; and aspects to consider when designing post-market environmental monitoring.