The first 100 days have great practical and symbolic importance for new leaders, whether in sport, business or politics.
Lord Coe, athlete and chairman of London's successful bid to stage the 2012 Olympics, marked the start of intense preparations by listing priorities for his first 100 days.
Mark Hurd, who replaced the ousted Carly Fiorina as chief executive of Hewlett-Packard in April, made his first big move after 110 days when he announced sweeping job cuts at the US information technology company.
Dominique de Villepin, the new French prime minister, promised that within his first 100 days he would restore voters' battered confidence with measures to tackle high unemployment.
These first three to four months offer a unique window of opportunity but they also pose huge risks, says Margaret Exley, UK chairman of Mercer Delta, the management consultants, in a paper entitled First 100 Days: the new CEO's challenge.
"Your formal decisions, informal behaviour and symbolic acts will be closely scrutinised by everyone with an interest in your company. Everything you do and say will send messages, set tone, establish expectations and communicate directions for the new leadership group."
Todd Stitzer, who became chief executive of Cadbury Schweppes in 2003, says there is huge pressure to announce a change of strategy and to make promises about future results, and new leaders are often openly encouraged to criticise the past.
"Resist this," he says. "Get out of head office and listen to colleagues, customers, consumers, share owners and the financial community to gain insights about your business. Study your company's past, your competitors, and other business paradigms to help divine your plan. Announce your strategy and plan only after intense reflection and analysis, making absolutely sure you've got your team behind you and they've been part of the creation."
Getting the right balance between analysis and action is crucial. A new leader who acts without thinking will create a backlash. This is the bull in the china shop syndrome, says Katie Beavan of Robert Schaffer Associates, a US management consultancy. In an article to be published in Across the Board, the Conference Board magazine, in December, she cites a senior executive who was promoted from a successful role in a European industry niche to head a business in Asia.
"On arrival, he quickly summed up what he saw as the issues, determining that the team was ineffectiveand complacent and that he needed to 'straighten things out'.
He let his team know that their performance was inadequate and told them how to improve it. He let his peers know that he had a better approach and complained about their incompetence when they challenged him."
Within two months, having failed to understand the complex political and business landscape, he had alienated his peers and subordinates and lost the support of his global boss. A few months later, he left the company.
There is a pervasive myth about the need for change, says Albert Zandvoort, director of the Top Leader Journey programme at Ashridge Business School. "The research we've done shows that often organisations function perfectly well and it's not necessary to make changes immediately. CEOs think there needs to be drastic change but often it just needs to be incremental."
Whatever the scale of change required, it is important that the chief executive acts decisively at the end of the first few months. "One of the things we have found is that the key contribution the chief executive makes is to redefine the purpose and sense of direction of the organisation," says Mr Zandvoort. "That should be done collaboratively. The days of the lone wolf are gone."
Peter Bakker, who became chief executive of TNT, the Dutch-based mail and logistics group, in October 2001, says he was fortunate enough to have a big event already in the diary for the following January. This was the annual gathering of the top 250 managers. If no such event is planned, he recommends that new chief executives engineer one. Not only did it concentrate his mind, it also allowed him some time out of the spotlight, as everybody's expectations were focused on the meeting.
Mr Bakker spent the time listening. "Anybody who thinks he or she needs to talk in the first 100 days runs the risk of missing a lot of opinions that could be useful later on," he says.
He also resisted bringing in consultants. "I felt that before we went to external sources we should tap the brain power inside the company. I made a list of the top 35 people throughout the world, in different regions, businesses and functions, and set up three-hour discussions with each of them."
He asked them about themselves, their businesses and what advice they had for him and the company. It was a useful strategic exercise that also symbolised the way he wanted to run the business.
"I got to see many different angles and sent a signal to the company that I was here to receive messages, not only to send them."
At the end of 100 days, his big idea was not a new product or market, but a decision to end the company's sponsorship of golf tournaments and form a long-term partnership with the United Nations World Food Programme. It marked a shift in values for the company.
Leaders need to have many attributes - the ability to inspire as well as to analyse, the ability to communicate, execute and govern. No one chief executive will have all these, says Jon Moynihan, chairman of PA Consulting.
"In the first 100 days, it's tremendously important to understand your own strengths and weaknesses and to get support for those areas where you're less strong."
The job will be very different from the one you came from. When Mr Bakker moved up from being chief financial officer he sought his fellow directors' views of the difference between the CFO and chief executive roles. While the chief financial officer could limit himself to financial performance, "they wanted to see the chief executive more involved with customers and employees".
Building a mutually respectful and trusting relationship with the board is also important if the chief executive is to be assured of its support in building the company's long-term performance in the face of financial market pressure for swift returns.
Once the consultation is complete, it is time for ashort, sharp analysis of problems that have surfaced, and for solutions, says Mr Moynihan. Assigning this task to special teams is a chance for the chief executive to try out talent.
The chief executive will direct these teams and needs to be very visible when it comes to deciding on solutions, while encouraging others to participate. Then it is time to deliver, drawing up plans to execute the decisions, whether buying or selling a business, changing personnel or installing new technology. The final stage is to communicate what is happening both internally and externally, which is where the idea of a 100-day event comes in.
Mr Stitzer has a final piece of advice: resist the temptation to pat yourself on the back as you make progress. "There's a lot to do in only 100 days," he says. And that is just the beginning.
Take the time to look, listen and learn before you leap
1. Do not rush into decisions or announcements before intense consultation and analysis. Do not get sidetracked. "Stay focused in the early days on creating your plan, developing a team and understanding your environment." (Todd Stitzer, Cadbury Schweppes)
2. Diagnose, decide and deliver. (Jon Moynihan, PA Consulting)
3. Share power. "The most powerful CEO is the one who expands the power of those around him." (Michael Porter, Jay Lorsch and Nitin Nohria, Harvard Business Review)
4. Seek advice from people who are "sympathetic but not sycophantic". (Lord Coe)
5. Avoid speculative discussions with employees - your half-baked ideas risk being taken up as good ones. Keep messages clear and simple and repeat them often. (Porter et al)
6. Keep white space in your diary for thinking and spontaneous consultation. Focus on the board, the executive team and employees. (Margaret Exley, Mercer Delta)
7. Familiarity can be a powerful obstacle to making tough decisions for an insider. (Exley)
8. For an outsider, the challenge is to establish credibility. "You will have to consciously reach out early in your tenure." (Exley)
9. Be prepared for the toll the job will take on your personal life. "Virtually every new CEO reports that relationships with friends and family have changed." (Porter et al)
10. Do not waste time on self-congratulation. (Stitzer)