Generally an interview is conducted to assess a) domain knowledge and b) personality traits/culture fit.
If you are appearing as IR professional, following are the areas where you should have knowledge- again the level of knowledge depends for which the level of the position.
1) Organizational and business awareness
2) Labour laws, factories act, States environment act, Basics of criminal law or criminal procedure, local self government related laws and procedures
3) Procedures- prescribed under different labour laws- ex. raising a dispute- handling conciliation,reporting of accident, issuing notice of change etc.
4) Legal compliance under different labour laws and its implications on organization
5) Court procedures
6) Liasioning-knowledge about who is wh0 -about local Labour, factory, environment and municipal corporation/panchayt
7) Dealing with union- communication, negotiation, counselling, persuasion tolerance, emotional intelligence, analytical skills etc
8) Handling settlement -provisions in ID act- various options available- detailed steps involved in settlement(collective bargaining)
9) Knowledge about various mandatory participative forums like works committee, safety committee,canteen committee etc.
10) Capability to handle crisis situation
11) Awareness abot current IR scenario- National, Regional and local
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