Official UK statistics from the Office for National Statistics, including the Annual Survey of Hours and Earnings.

European Commission webpage with some useful information. The Fawcett Society also carries out research on this topic for the UK,
as does the OECD for OECD countries (data from 2000-). See the Gender Pay Gap report from UK Parliament published as HC 584, session 2015/16. ONS has Gender pay gap tables from the Annual survey of hours and earnings.

Source of data on graduate starting salaries, published in its Graduate Market report.

Section on Forced Labour, Modern Slavery & Human Trafficking

UK quango advising the government about the national minimum wage. See also the Living Wage Commission and Living Wage Foundation.

Coordinated by the Chartered Management Institute and XpertHR.

Accounting giant does research on executive pay & other areas.

International project, based on research by Piketty, Atkinson & others, providing data on various aspects of income for a growing number of countries worldwide, with statistics back to the 19th century in some cases.