The 4th Edition of the Offshore Risk Assessment was published by springer around 1st October 2019, marking the 20 year aniversary for the publication of the 1st Edition in 1999.

A new chapter on Normally Unmanned Installations (NUI), also covering the future Unmanned Production Platform (UPP), is the significant extension of the manuscript, in addition to numerous updatings of statistics and topics.

The authors are grateful for the financial support from Dept of Marine Technology (NTNU), who financed a summer student in 2018 to assist in the manuscript preparation.