Deputation, concept of 'deputation' is well under-stood in service law and has a recognised meaning. 'Deputation' has a different connotation in-service law and the dictionary meaning of the word 'deputation' is of no help. In simple words 'deputation' means service outside the cadre or outside the parent department. Deputation is deputing or transferring an employee to a post outside his cadre, that is to say, to another department on a temporary basis. After the expiry period of deputation the employee has to come back to his parent department to occupy the same position unless in the meanwhile he has earned promotion in his parent department as per Recruitment Rules, State of Punjab v. Inder Singh, AIR 1998 SC 7 (15): (1998) 7 SCC 372.
'Deputation' can be aptly described as an assignment of an employee (commonly referred to as the deputationist) of one department or cadre or even an organisation (commonly referred to as the parent department or lending authority) to another department or cadre or organisation (Commonly referred to as the borrowing authority). The necessity for sending on deputation arises in public interest to meet the exigencies of public service. The concept of deputation is consensual and involves a voluntary decision of the employer to lend the services of his employee and a corresponding acceptance of such services by the borrowing employer. It also involves the consent of the employee to go on deputation or not, Umapati Choudhary v. State of Bihar, (1999) 4 SCC 659: AIR 1999 SC 1948 (1950). [Bihar Sanskrit Education Board Act, 1982 (31 of 1982), s. 5]