When you arrive in Thailand you will automatically receive a "visa-on-arrival", which allows you to stay in Thailand for up to 30 days without a problem. Should you need to stay longer than that, you will need to renew your arrival stamp. You can do this for up to 90 days.

This may sound easy enough, but let me explain a little further... Thailand immigration allows you to use a "visa-on-arrival" to stay in Thailand for up to a total of 90 days, but never exceeding 30 days at a time. So, if you plan to take several trips in and out of Thailand, you really have to keep a tally of your days - and remember that the maximum is 90. If you are here on holiday and decide to stay for more then 30 days, keep an eye on the date of your stamp (it may not be exactly 30 days), and be sure to renew the stamp when it expires. And again, you can do this for a maximum of 90 days. In theory, this means that you will be able to renew your 30 day stamp three times, but because of the variation of the 'stamped' days, this may not work out exactly.

After these initial 90 days, you will then have to obtain a tourist visa (there are other options such as a business visa or a work permit, depending upon your situation). I know this sounds complicated, but there are a number of companies that will help you (for a fee, of course). Most offer a day trip to a local international border, like Cambodia, Laos or Burma (Myanmar). The company will take care of the visa requirements for the country for which you are headed, and will often tell you what to expect at the border, maybe even also providing lunch and refreshments.

Your first trip into one of these countries can feel a bit unnerving, especially as you travel from the developing country of Thailand into an undeveloped country such as Cambodia. Cambodia is poor and the begging at their border crossings is quite pervasive. It may sound hard, but the begging will only get worse if you start to give.

Personally, I like to go to the border crossing in the province of Chanthabury in Ban Laem. I like this border crossing, mainly because it is the closest to Bangkok and they generally have you back in Bangkok at a reasonable hour. The roads leading to the border are quite well maintained, but the roads in Cambodia are more like rough tracks, which are dirt or mud depending upon the weather.

In Ban Laem, you walk across the border on a small wooden bridge. If you are going there to renew your visa you will not actually enter Cambodia. Instead, your passport will be collected so that it can be stamped with your Cambodian Visa, and while you wait you will be guided into a transition zone. The zone is located in a small area on the border, here you can buy inexpensive contraband, such as liquor and cigarettes and maybe even have a bet in the casino.

I hope my description of the situation will give you some idea of what to expect. Everyone speaks pretty good English and the crossing is completely safe. Below are some photos of the Ban Leam Border crossing to help you further.

If you find that you have overstayed your visa, please don't panic. Whatever your situation, I recommend that you seek out a specialist visa company – there are many of these located in the main tourist areas throughout Thailand. The better of these companies will also offer consulting services; answering all sorts of questions and providing help to those in unusual circumstances – most situations can be worked out without ending in deportation. You may just have to pay some extra Baht. Keep in mind that, after all, Thailand welcomes your visit because tourism helps to boost the economy. Here are some websites that you may also find helpful:

• Sawasdee Transport Service Co. Ltd, Bangkok, Thailand for Visa Run Service - Bangkok to Ban Laem, Cambodia
• Thailand Expat Forum - for alerts, news and visa information.