Here would be a couple of points to reduce threats in security for your small business.
Try to scrutinize your employees before hiring them. You might want to check their personal references and a conduct a background check. Like the common preventative measures, it would be less expensive compared to having to deal with the bad subsequences. However, it would take time.
Limit the access that your employees have to your company data and server. If you have a server room which is regularly locked, however the person who keeps the key to that room keeps it on his desk which is accessible by anyone, then what you are doing is pretty much useless.
Require your employees to use good password, which should be regularly changed. This may cause some negative reactions, but it would prove to be a security measure that would be valuable in the long run.
Make sure that your data is backed up regularly. It would be advisable to backup company data daily, if possible. And at weekends, you would also need to do a backup, which would be taken off site and then stored.
Invest on a virus protection software, as well as a digital intrusion detection software which must be installed and reviewed regularly. If you would be outsourcing your IT services, the company which would be providing these services should also be able to provide a virus protection software this for you.
Although it could be possible to go a bit overboard on the security measures, which you would be using, there are actually a handful of companies who do so and a lot do not even have a basic security plan in place. If your business is important to you, it would definitely be important to invest in an excellent and effective business security coverage.