Somewhat unsurprisingly, having an affair with a colleague tops the list of seven deadly business sins newly-appointed bosses should avoid at all costs.

First100, a company which specialises in leadership performance acceleration, has compiled the following “seven deadly business sins” for those starting out in a new role:

1. Don’t sleep with a colleague – unless you are married or in a relationship with them!
2. Don’t keep referring to “how we did things in my old company”
3. Avoid too many introductory meetings which you can’t follow up
4. Don’t make decisions just for the sake of being decisive
5. Don’t avoid sacking someone in the hope they’ll work out – they rarely do
6. Don’t avoid playing the political game – everyone else is at it
7. Avoid telling staff you’re going to spend your first 3 months asking questions.

First100’s Garrett O’Keeffe said: “The first 100 days in a new role are important in so many ways. Get off to a good start and a boss can set the tone for the rest of their time at an organisation, but equally the opposite applies. “We have worked with hundreds of companies during the past six years and our list of seven sins in your first 100 days is based on our experiences. “Starting in a new senior role is a highly pressurised time and it is crucial that bosses put in place a proper plan with clearly defined objectives for their first 100 days and beyond. “A good leader will have a clear vision, have no fear, be a fast learner and know when to show patience and resilience.

“Without a clearly defined plan for the first 100 days, it is easy to fall into the trap of holding lots of introductory meetings, asking endless questions and talking about how good things used to be in their old company. “These are some of the biggest blunders new bosses will make and the result is that the first 100 days will have gone and very little will have been achieved. The first 100 days in a new role is a critical time period and will have an impact for the next 12 months and beyond. “A

chief executive or senior business leader struggling to get to grips with their new role can further massively compound any problems if they are tempted to have an affair with a more junior colleague. “Life at the top can sometimes seem a lonely place which probably goes a long way to explaining why some of our leading public figures are tempted to stray, but the potential long-term damage to an organisation both internally and externally is immense.” Examples of this include former RBS chief executive Sir Fred Goodwin and ex-England manager Sven Goran-Eriksson, who both had high profile relationships with more junior colleagues.