Professionals are targets for identity theft as they generally have some savings, lots of important documents, and do a lot of mailing. Identity theft is growing with according to the Bureau of Justice Statistics 16.6 million people becoming victims every your. There are ways to protect your data to ensure that you are minimizing the damage. Taking a few preventative actions can help but won't get rid of theft.
There are no fool proof systems of protecting your data other than to not have any which is something pretty difficult to do. Mistakes are always made. Recently I went to a mall and within a few minutes someone grabbed my backpack out the backdoor of my vehicle. It didn't take them but a few seconds and I immediately went into damage control mode calling the police and my bank.
One of the best ways is to get a shredder and never put important documents in the waste basket. Criminals will dig through the garbage in order to get documents. They are seeking your social security number, old checks, bank account information and other documents that can help them get some of your money.
Don't always trust the people you know. Roommates, family, friends, and neighbors are some of the biggest perpetrators. They take advantage of your niceness and closeness to get documents. Even if they didn't start out this way they will inevitably come across something they can monetize on and could eventually steal it. Try and keep important documents locked away and out of site.
Don't expect these issues to get resolved and if you do happen to find out who did don't expect any remorse. Police departments are flooded with these issues and many times they cross state and national borders. When they are resolved confronting the person does no good because they cannot see what they did as wrong. More likely they will blame you. The best defense is be proactive with your documents.