Four IT vendors are among the top 10 firms in this year's World's Most Respected Companies list from PwC.

Microsoft moves to the top of the list from second last year, while IBM moves to fifth from fourth last year.

The new entrants to the top 10 are Apple, the highest climber at ninth from 42nd, and Siemens in at 10th position from 23rd.

Google is another high climber coming in at 39th from 58th last year, while HP suffered the greatest drop, from 10th to 46th.

Bill Gates remains the number one most respected business leader and in a new listing of 'most influential business writer or management guru' comes in at second just behind management guru Peter Drucker.

Microsoft is also rated top in the 'best for shareholder value' category and perhaps controversially in the 'best for innovation' category.

IBM and Apple were also placed in the 'best turnaround' category.

The eight year-old survey is based on 1,000 chief executive interviews. Results are weighted according to the GDP in each country.