Do your research and check out the gossip
For any job in the Middle East, you will need a contract from your employer - usually issued in your home country - which is then used to obtain a work visa.
Work visas are usually time-limited and in some countries are linked to the job, so it is not always possible to move to a different employer. In certain parts of the Gulf, however, this can be done with agreement from your current employer. Applicants will generally have to pass a medical.
In some cases, your employer will sort out everything for you, including visa, accommodation, healthcare and even your children's school. In other cases, particularly with smaller companies, you will be required to sort out much more yourself, often working with an allowance.
As everywhere, there are occasionally unscrupulous employers who will bend or even break the law. Although such cases are rare, it can be expensive, complicated and time-consuming - but not impossible - to take legal recourse for, say, missing salary.
To avoid any problems, do as much research as possible on prospective employers. Forums such as Pprune (Professional Pilots Rumour Network) are good for gossip - but beware of malicious postings.
Plenty of country-specific advice is available on the web about working in the Middle East. Justlanded.com and theemiratesnetwork.com are especially useful.
Once you are based in the Middle East, you will find the gossip network - with colleagues, friends and neighbours - the best way to pick up advice on everything from schools to finding new accommodation.