Who ships to Guam (US)?
Lynden is a logistics company that handles air cargo shipping to Guam. DeWitt Moving and Storage can help you with both shipping and storage in Guam if you need that service. Matson Navigation company specializes in shipping vehicles to Guam, but they can ship other things as well. CTSI Logistics and Global Shipping both ship to Guam, as do FedEx and UPS.
Security concerns when shipping to Guam (US)
There really isn't much reason for concern over safety when shipping to Guam as they have a fairly good track record of getting your packages delivered to their new homes. There, of course, have been some lost or stolen packages, but not often enough that it seems like a pattern that you should be concerned with when sending something there.
Shipping destinations in Guam (US)
You can get your shipment to anywhere in Guam you want, even if your package is handed off to a local company for the last leg of its journey which does happen from time to time. This practice occurs very often, not just in Guam, so be sure to specifically ask you shipping company if this is the course they take when booking your shipment with them if you care about this fact. It is also important to note that if you ship from the continental United States, you will typically be charged for international shipping when shipping to Guam even though it is a US territory just like you would be when shipping to Puerto Rico or Hawaii.
Tracking your shipping to Guam (US)
Getting a tracking number for your package when shipping to Guam is a smart move. This way you can see where your package is in transit and know when it gets to its intended recipient. You can also get a delivery confirmation returned to you as well.