Few of us enjoy waving a cheery goodbye to our luggage at the airport as we see it trundling through the flaps behind the check in desk and disappearing into the strange land beyond. When we reach the other end, the creeping doubt about whether we will ever see it again, or whether it will have been damaged, or broken open, or even stolen, will always be in our minds. The relief of seeing our own case appearing, intact and safe is wonderful.
The truth is that our luggage is never secure once it leaves our own possession. There are a number of things that can happen to it, including accidental damage, theft, and of course the risk of it being forced open by security if you have locked it, and they need to inspect it for whatever reason.
There are a number of things to bear in mind to help you reduce the risk to your luggage. The first is obvious, but quickly dismissed by most people. Rather than carrying a suitcase with you, why not see if you can reduce your essential possessions to the size of a carryon bag. If you can manage to fit your items into one over the shoulder carryon bag then you will never have to part with your items. It is very surprising to discover just how little you actually need to take with you to be able to enjoy yourself fully on holiday. Taking endless changes of clothes simply takes up room. Do you really need to take clean clothes for every day? Are there no washing facilities where you are going? Professional travellers, such as reporters for example, will often only have one or two bags that they can easily carry with them at all times. There are plenty of sites and articles about how to reduce your luggage quantity.
Locking your case is always a good idea, although in some countries there can be a risk that security will break open the lock or force open the case if they need to inspect it. The tip here is to make sure that you don't carry anything in the case which might cause suspicion - such as liquids, metal items and so on. Also, it might be worthwhile, if you use a padlock to lock your case, to take a spare with you, in case.
The biggest security issue is actually the humble zipper. Most flexible bags have zippers, and very often they come with small padlocks or fittings to allow a padlock to lock the bag. However, if you have ever experienced a zipper breaking open on a cushion cover or coat, you'll already know how easy it is to force a zip open at one end. A ball point pen is all you need to push open one end, after which the zipper will merrily undo along its full length, allowing removal of almost the whole contents. For over the shoulder bags you carry with you, these are fine, but for bags which will to be in your possession the whole time, zips are something to be wary of.
One other point to mention - if you have a bag that looks as though it is easy to carry over your shoulder, you are far less likely to have it weighed than if you are struggling with two or three around you, along with a case. In this respect, you can often get away with a little more than you might otherwise be allowed!