Travelling by plane is a very quick method of travel in theory. Once you're on the plane, a journey from say Glasgow to London could take around an hour and cost you around £110 from British Airways (If you want the cheapest flight it's a good idea to look on sites like travelsupermarket.com.)
Don't forget however, that most airports ask you to arrive around an hour or two earlier than your flight for security checks which can add to your travel time. The cancellation or a delayed status of your flight can also be very problematic if you need to arrive at a meeting.
Train journeys can face the same problems, minus the security checks however railway stations are usually much more central, perfect for reaching the office if these don't occur. Travelling by train can be practical for those of you who need to catch up on some work where you have the option to sit in first class and use the internet.
Ticket prices can vary dramatically for train travel and they are usually best booked in advance to ensure a cheaper ticket. Ticket prices are usually similar to plane tickets but it will usually take a lot longer to get from A to B.
Car hire can be very comfortable and it means you can plan and time your journey without worrying about delays or cancellations. You have comfortable, adjustable seating and if you're travelling with another person you can switch up the driving and take it in turns allowing you to have a rest. If you're travelling alone however, and your trip takes a long time then you may become tired.
The cost of car hire is very cheap too. For a week you can rent a car with Hertz for around £110, (don't forget the cost of petrol to get you to your destination); however this way you can use your car hire for other journeys you have been meaning to take too, as well as for your all important business trips. Prices may also be a lot cheaper if you only need the car for a day or two.
