According to National Retail Federation statistics, retail establishments lost $41.6 billion dollars in 2009. Included in that amount is $19.5 billion of employee theft -- or 47 percent of the total loss suffered. With statistics like that, you can't be passive. Passivity will result in profit loss for your business. By being proactive, you can reduce employee theft -- specifically from employees who are stealing from the cash register.
Assign one employee to each cash register drawer instead of allowing multiple employees to use one drawer. The more hands you allow in the drawer, the more difficult it is to determine which hands are guilty of stealing.
Use electronic surveillance to monitor each cash register drawer. It can be expensive to have an electronic surveillance system installed. If you don't have a lot of money to invest on surveillance, purchase a small surveillance camera that can be hidden near each cash register drawer. Hidden cameras can be purchased from local and online electronics supply stores.
Place extra cash in the cash register drawer before the employee pre-counts it. For instance, if the employee's pre-count is supposed to be $150, place $170 in the drawer. If the employee is a thief, he will pocket the extra $20. When you count the cash register drawer at the end of the night, if the extra money is consistently missing, it is an indication of theft.
Have an individual (a "secret shopper") make a purchase at the employee's cash register. When the employee gives the change back, have the secret shopper give a few extra dollars back to the employee. The secret shopper can tell the employee that he received too much change back. When you count the cash register drawer at the end of the night, the overage should be there. If not, it is an indication of theft.