The Samos Island (Aegean Sea) earthquake struck at 13:51/14:51 local time in Greece and Turkey, respectively, on 30 October 2020. It produced wide-ranging effects including tsunami run-up, ground shaking with local zones of high intensity that produced collapsed structures and 118 fatalities in both countries, and various geotechnical effects including liquefaction and landsliding.

The earthquake occurred during the global COVID-19 pandemic, which necessitated a different response than would be typical for an earthquake of this size. With global travel restricted, international agencies did not send reconnaissance teams to the region. However, reconnaissance was performed. In Greece, the Hellenic Association of Earthquake Engineering (HAEE/ETAM) mobilized a 12-member team to Samos Island and neighbouring islands in two successive missions, which included a US faculty member who was in Greece at the time (K. Ziotopoulou). Similarly, the Earthquake Engineering Association of Turkey and Earthquake Engineering Foundation of Turkey (EEAT) mobilized teams to affected regions of the Aegean coast, with the main focus being the highly impacted city of Izmir.

This special issue and a combined report published in December 2020 (Cetin et al. 2020) are the result of an unprecedented collaboration of the aforementioned Greek and Turkish organizations, along with US-based professional societies and reconnaissance organizations, including the Earthquake Engineering Research Institute (Learning from Earthquakes program) and Geotechnical Extreme Events Reconnaissance Association (GEER) (Cetin et al. 2021a). This special issue presents a coordinated series of papers relevant to seismological aspects (Akinci et al. 2021; Kiratzi et al. 2021), ground motion data (Askan et al. 2021), geotechnical findings (Ziotopoulou et al. 2022) and site effects (Cetin et al. 2021b), seismic performance of buildings (Yakut et al. 2021; Binici et al. 2022) and lifelines (Toprak et al. 2022), tsunami triggering (Kalligeris et al. 2021), as well as wider emergency response (Mavroulis et al. 2022) and social impacts of this important event, both on the Greek islands and the Turkish mainland.

On behalf of the sponsoring organizations, the special issue editors would like to express their gratitude to the individual paper authors and reviewers that made these important research contributions possible.