If you are responsible for maintaining a company’s accounts, situations where there is less money than there is supposed to be are probably going to be far less than ideal to say the least. The truth of the situation is that money not being where it was expected is going to be a huge hassle for you because of the fact that you would have to justify what you are currently seeing, and this is probably going to cause a lot of problems for you so your top priority would be figuring out what just happened especially if this is a situation where you are the owner of the business and you are trying to make it so that no matter what happens you can get the most out of this particular situation all in all.
If money has gone missing there is a pretty good chance that someone has stolen it and this usually happens with someone within the company itself, someone that had access to the funds and appropriated them for personal use. Finding out who did the deed might not be all that useful however, so you might want to try and look into LaSorsa & Associates to hire a private investigator that can help you out a bit along the way.
This investigator will be able to see if anyone has been making any extra expenditures in recent weeks and months, this will indicate that that person has a source of income that they are not telling you about which makes it likely that they might just be skimming funds all in all. The best thing to do is get the evidence and then take your findings to the police.