The best defence against shoptheft is providing the best customer service possible. Killing potential thieves with kindness is the most economical tactic. By doing so, you can change the mindset of someone preparing to steal from you. On the other hand, inactivity can encourage theft. Properly trained and attentive sales associates are your best assets.
Management sets the example.
You must also follow the code of conduct you establish for your staff. Greet everyone entering your store or sales area. During office meetings, conduct role-playing scenarios that include confrontations in order to demonstrate expectations and conflict resolution. No one is paid to get hurt. Good business practices would suggest that only well trained in-house or contract retail investigators should be involved in arrest situations.