Outside of the legal paperwork, the manager may include via email or call, a message welcoming the new employee to the team, an overview of the department/division and the purpose, and even an org chart to get the new hire acquainted with the organizational structure.
Finally, if an exception to the offer has been extended, ensure it is in writing and added to the personnel or HR employee file and that payroll is aware of any exceptions, such as additional benefits or PTO time.
Quizzes