Originally the work on the ISC-GEM Catalogue was requested and funded by the GEM Foundation as one of the five GEM Global Hazard Components. Further resources towards this work were provided by the ISC.

We acknowledge several hundred research and operational institutions around the world for providing on a goodwill basis paper-based seismic bulletins to the ISC and its predecessors regularly over the course of the 20th century.

We gratefully acknowledge the financial support given by all ISC Member Institutions to sustain the operations of the ISC and its predecessors.

We acknowledge the advice and guidance received from the group of IASPEI observers that included Göran Ekström, Roger Musson, Johannes Schweitzer, Nobuo Hamada and Peter Suhadolc. The group provided invaluable advice on the details of the GCMT Catalogue and the uncertainties of the GCMT magnitude determinations, the availability of historical bulletins as well as documents and details of historical seismographic equipment.

We acknowledge Japan Meteorological Agency (JMA) and Nobuo Hamada for providing previously unavailable early instrumental (1923-1970) bulletins of earthquakes in Japan. We are grateful to Katsuyuki Abe for providing a digital copy of the Abe and Noguchi Catalogue.

We are grateful to USGS for providing digitally scanned and paper based seismic bulletins from its collection.

We wish to recognise the initiative of the late Edouard Arnold and Patrick Willmore, former Directors of the ISC, for transferring a large proportion of the ISS paper bulletins onto punch-cards and preparing the Shannon tape, despite the financial difficulties experienced by the ISC at the time. We also acknowledge the effort of Tom Boyd, Colorado School of Mines, for further correction of this data.

We thank Robin Adams and David McGregor for providing historical information on the operations in the early years of the ISC.

We are grateful to Anna Berezina and Kanatbek Abdrahmatov (Institute of Seismology, National Academy of Sciences,Kyrgyzstan) for organizing the scanning of the original operator notepads of the seismic station Frunze.

We thank Aleksey Malovichko, Oleg Starovoit, Irina Gabsatarova, Olga Kamenskaya, Vera Babkina, Raisa Mihailova and Elena Terehova (Geophysical Survey, Russian Academy of Sciences, Obninsk, Russia) for providing digital files and scanned images of the bulletins of the United Backbone Network of Seismic Stations of the Former Soviet Union and individual historical seismic stations of the Russian Empire.

We are grateful to Siegfried Wendt (Universitaet Leipzig, Germany) for sending us missing bulletins of the Collm Observatory; Jina Gachechiladze (Ilia State University, Tbilisi, Georgia), Arkady Aronov and Vladislav Aronov (Centre of Geophysical Monitoring of the National Academy of Sciences, Belarus) for providing positions of historical sites of seismic stations of former USSR.

We thank Jon DeBord and Chuck Wenger, USGS Librarians, for their assistance in searching through the scientific literature and arranging inter-library loans.

We are grateful to the ISC staff that dealt with the multitude of technical issues: Maureen Aspinwall for dealing with the project finances, Oriol Gaspa Rebull for developing the data entry web browser interfaces, Przemek Ozgo for implementing these webpages, Wayne Richardson for offering advice on historical bulletins and, most importantly, Rebecca Verney, Natalia Safronova, Rosemary Wylie, Jessica Wilson, Agne Baranauskaite and Hepsi Simpson for their enormous manual effort of typing relevant arrival time and amplitude data from the historical seismic bulletins stored in the ISC warehouse.

Finally, we gratefully acknowledge the use of Google Maps and Generic Mapping Tool (GMT) in numerous presentations, posters and scientific articles explaning the nature of the ISC-GEM Catalogue.