Abstract In Search and Rescue (SAR) operations, the First Responders (FR) are called upon to act in a wide range of environments, conditions and limitations, associated to both external and internal factors. Weather, location, access, infrastructure, travel time, are only some of these external factors, while team’s readiness level, organization, skill level and experience, toolkits available, are some of the most important internal factors. For Urban Search and Rescue (USAR) the most critical factor, besides FR safety, is speed. Every USAR mission is an effort against time, beginning as a speed race during the first few hours after the disaster event and gradually becoming a marathon run as the hotzone gets cleared in a more focused way. Lack of preparedness, coordination and poor perimeter monitoring is, as expected, a major factor in large-scale disasters. Specific differences in task prioritization and speed are evident between small-scale events like train accidents and large-scale events like devastating earthquakes, leading to corresponding changes in the deployment or even the planning phases of a SAR mission. Citizens and spontaneous volunteers are important assets often overlooked. The “last mile gap” and changes in First Aid / medical response are also crucial factors that emerge more evidently as the scale of the disaster increases. In the non-operational context, a few important guidelines and good practices can be proposed for SAR-related R&D projects. Specifically, several limitations and hindering factors in developing new technologies may work counter-productively, often very early on while in design or prototyping phases. These include very limited or no provision budget-wise for full IPR protection of the developed technologies, the low Technology Readiness Level (TRL) expectancy, limited focus to standardization and interoperability outcomes, as well as the inherently limited / highly specialized FR “market” for these products and tools. Based on the experience from DRS cluster projects of EU Horizon H2020 in recent years, important guidelines and good practices can be formulated in relation to expectation management for both FRs and technical partners, early end-user involvement in all the phase and extensive field trials throughout the projects’ lifetime.