In general, business visitors include:

• academic visitors (may enter or stay for 12 months maximum, subject to entry clearance if over six months);
• doctors taking the professional and linguistic assessment board (PLAB);
• doctors coming for clinical attachment or dentists coming for observation;
• Visiting professors accompanying students undertaking study abroad programmes (see guidance for further information);
• film crews on location shoots only, provided they are employed or paid by an overseas company;
• representatives of overseas news media, provided they are employed or paid by an overseas company and are gathering information for an overseas publication or programme;
• secondees from overseas companies;
• religious workers undertaking some preaching or pastoral work during a business visit (for example, to attend a conference), provided their base is abroad and they are not taking up an office, post or appointment;
• interpreters and translators employed by an overseas company who are coming to the United Kingdom solely to accompany and provide a service to business visitors from the company;
• advisers, consultants, trainers or trouble shooters employed abroad by the same company to which the client firm in the United Kingdom belongs, provided this does not amount to employment paid or unpaid for the United Kingdom branch; and
• persons undertaking specific, one-off training in techniques and work practices used in the United Kingdom 

As a business visitor, you will only need permission (known as 'entry clearance' or 'a visa') to come to the United Kingdom for a business visit of up to six months if you are a visa national. See Section Visas to the UK in the right-hand menu on this website. If you are a non-visa national, permission to come for up to six months is not needed as a business visitor. If you are an academic visitor and want to come for more than six months, you will need permission to come whatever nationality you are. Multiple entry visas are available for business visitors for six months, and one, two, five and 10 years. To come to the United Kingdom as a business visitor you must be able to show that you: 

• only want to visit the United Kingdom for up to six months;
• plan to leave the United Kingdom at the end of your visit;
• have enough money to support and accommodate yourself without working, help from public funds or you will be supported and accommodated by relatives or friends;
• do not intend to charge members of the public for services provided or goods received;
• do not intend to study;
• can meet the cost of the return or onward journey;
• are based abroad and have no intention of transferring your base to the United Kingdom even temporarily;
• receive your salary from abroad.

If you intend to work longer than six months, you may come to the UK under the intrepreneur or investor category.

The entrepreneur category is for those investing in the United Kingdom by setting up or taking over, and being actively involved in the running of, one or more businesses in the United Kingdom. You can apply under the entrepreneur category now if you are:

• in the United Kingdom and want to make an initial application as an entrepreneur; 
• already in the United Kingdom as an entrepreneur and want to extend your permission to stay within your existing category;
• already in the United Kingdom as a business person or innovator and want to extend your permission to stay in the entrepreneur category;
• applying for permission to enter the United Kingdom (known as 'entry clearance') under the entrepreneur category. 

The investor category is designed to allow high net worth individuals make a substantial financial investment in the United Kingdom. Unlike our work permit scheme (soon to be replaced by sponsored workers (Tier 2), you do not need a job offer to apply under the investor category. When you apply you are awarded points based on your ability to invest £1,000,000 in the United Kingdom.

For any further information on doing business in the UK, please consult the UK Border Agency website by following the link http://www.ukba.homeoffice.gov.uk/workingintheuk/tier1/.