On February 14, 2020, Nicholas G. Martin, the Editor of Twin Research and Human Genetics, celebrated his 70th birthday. While many of his contemporaries are enjoying their retirement, Nick shows no signs of slowing down, having just received a prestigious 5-year National Health and Medical Research Council of Australia Investigator Grant. We therefore thought it might be prescient to compile a special edition of the journal focusing on his life works.

In compiling and editing this compendium of commentaries and anecdotes about how Nick has influenced (and continues to influence) the field of complex trait genetics, a number of consistent themes and highlights emerged:

• his founding of the discipline of human complex trait genetics in Brisbane and Australia more broadly;

• his founding of the Australian Twin Registry and the Brisbane twin resource;

• his generosity of spirit with respect to scientific ideas, authorship and unconditional sharing of vast data resources among collaborators;

• his intellectual and financial generosity as a supervisor and mentor;

• his incisive mind and intellectual curiosity;

• his lasting contributions to the development of statistical methods to model human resemblance;

• his leadership and major contributions in the world of genomewide association studies;

• his tongue in cheek (at least we think) political incorrectness.

In the following pages, we and others have tried to document the myriad ways in which he has influenced the field of complex trait genetics and changed the lives of the many students, employees, mentees, colleagues and collaborators he has worked with.

Given the hundreds of scientists he has collaborated with over his career, inevitably there will be some who we have missed, who will have wanted to contribute their own anecdotes and stories about how he has influenced their careers. Indeed, during the course of compiling this tome, many more individuals came forward wishing to contribute, and we have done our best to include them here. For those whom we have omitted, we apologize and take full responsibility for the oversight. Indeed, the fact that this issue is so long and contains so many contributions is testament to the influence he has had!

Happy 71st year Nick. We do hope you enjoy reading the multitude of ways in which you have influenced the field of complex trait genetics and made major positive impacts on the lives and scientific careers of so many. Indeed, your legacy is not only a broad list of major scientific achievements in the field and the wonderful resources you have founded, but your intellectual F1s and F2s (some of them genetically related!), many of whom have returned to Brisbane after extended stays abroad, and are now leaders in the field in their own right.

Compiling and editing this tome has certainly been ‘a good exercise for us’.

David Evans, Sarah E. Medland and Nathan Gillespie, on behalf of the many contributors.