In the United Kingdom, McKesson (operating as McKesson Information Solutions UK Ltd) was a provider of information technology services to the health care industry. In addition to numerous clinical software systems and finance and procurement services, McKesson also was responsible for developing the Electronic Staff Record system for the National Health Service which provided an integrated payroll system for NHS's 1.3 million staff, making it the world's largest single payroll IT system. McKesson Shared Services also provided payroll services for over 20 NHS Trusts, paying over 100,000 NHS members.