There are two points to consider here, 1. You should have a company handbook or policy that states that the company / organisation audits computers for software. 2. Communicating with the staff why you are doing something.

If you supply home working staff software for their own computer then you are entitled to provide a service to ensure it is up to date.

The "usage" is virtually immaterial if you read License Agreements it is based on "INSTALLED" software not "USED" software.

When using company assets employees should have no expectation of privacy. If they are using personal computers to do office work, then the organization is mixing and matching their licensing issues. The risk to the organization of security breaches and software licensing violations is considerable. Each violation can cost the the company lots of money - consult the BSA and RIIA fine structures for yourself - and, you'll still have to "true up" with the software publisher anyway.

Plus, IT asset management data is fundamental to understanding and controlling IT costs so that your IT organization can demonstrate alignment with business services objectives.

IT Asset Management is one of those fundamental "run the business" activities that is poorly done because it's not sexy - yet, according to Gartner, "customers that commit a minimum of 3 percent of their annual operating budgets to ITAM programs and tools can expect a 25 percent reduction in their total cost of ownership."

A high risk of not doing ITAM, and a big payoff for doing it well. The first step is to get some help understanding what the possibilities are. The failure rate can be high for those that don't fully understand the commitment needed to achieve a proactive solution.

Good point - tracking disconnected equipment can be a real headache, and there's no perfect solution. The choices are to perform a manual inventory, use a remote inventory client (an agent run on a disconnected computer from a floppy, CD or other media), use a network client to collect data when machines reconnect to the network, or use RFID/barcode tagging. Of course, these methods each have their own pitfalls... Manual inventories are incredibly time-consuming, error-prone and non-dynamic; remote inventory clients need to be run manually and don’t address the issue of “missing” devices; network clients only work when machines reconnect to the network and therefore don't take into account systems sitting in storage closets or on loading docks; and RFID tagging tracks movement of machines but does not transmit critical software inventory or hardware information for individual PCs (plus, it's expensive and requires manual work to tag the equipment in the first place).

At the end of the day, companies need to develop IT asset management processes by which equipment details and locations are documented and maintained "from cradle to grave". This might include, for example, a "discovery" tool that tracks current inventories of all networked hardware and software, as well as processes that are kicked off when new equipment is purchased, retired, and/or moved, notifying the people that need to track this information. IT asset management tools can help, but they will never supplant robust, carefully-planned documentation processes.