As I look out across the ocean, savoring another sunset on Necker Island, I find myself reflecting on a busy and exciting year for myself and the Virgin Group. There were a couple of setbacks: In January, I ruptured a cruciate ligament in a ski accident, which meant that I had to travel to France and South Africa on crutches; in August, a fire here destroyed the great house. But we have ended 2011 in a much happier way, with my daughter Holly's wedding to Fred Andrews, a shipbroker. This seems a good time to jot down a few of the year's highlights.

I have written previously that success cannot be measured in wealth, fame or power, but by whether you have made a positive difference for others. The accomplishments of the past year of which I am most proud involve my efforts to raise awareness of and financing for Virgin Unite, along with the new philanthropic ventures we launched.

Because it is our responsibility as entrepreneurs and business leaders to tackle the issues our society faces, from climate change to poverty. To find solutions, we at Virgin have had to consciously cast aside traditional thinking, form unusual partnerships and consider unorthodox answers. Here are some of our most effective actions:

1. Taking the initiative.
The Carbon War Room is a business-focused, global NGO we set up three years ago to find profitable solutions to tackling climate change: Our society does not have to make a choice between economic growth and saving the environment. CWR is a nonprofit fixated by profit.

We made great progress over the past 12 months. Rather than waiting for governments to work out policy solutions, the CWR team launched two game-changing websites: one to promote efficiency in shipping; another to rank and chart the latest in sustainable aviation biofuels.

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Earlier this year CWR launched a program to help finance energy-efficient retrofits of buildings, which was kicked off with a
$650 million investment scheme in Florida and California.

2. Reducing, reusing, recycling and planning for the future.
We must also ensure that we conserve our planet's resources and maintain diversity. This year Virgin Unite struck up a great partnership with WildAid to campaign for the banning of shark-finning, the barbaric and wasteful act of cutting a fin off a living shark.

WildAid estimates that 73 million sharks per year are killed for this dish.

This project is in its early days but we are making great progress, thanks in part to the support of Governor Jerry Brown of California, who signed a bill banning the sale and possession of shark fins.

Already, many top restaurants and hotels no longer serve shark-fin soup.

3. Championing unconventional solutions.
Over the past 50 years, drug usage has gone up and jails have filled.

Though millions of taxpayer dollars have been spent trying to stamp out this illicit trade, the prohibitions have merely fueled organized crime. It is time that we try an alternative approach. This year I was fortunate to be part of the U.N. Global Commission on Drug Policy, which found that the costly war on drugs has backfired, producing little to no results.

A decade ago, Portugal became the first European country to officially abolish all criminal penalties for personal possession of drugs -- a brave and successful policy. Jail time was replaced with offers of treatment for addiction: many critics feared this would attract "drug tourists" and exacerbate Portugal's drug problem.

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The results of a report commissioned by the Cato Institute in April this year suggest otherwise. It found that in the five years after personal possession was decriminalized, illegal drug use among teens in Portugal declined and rates of new HIV infection caused by sharing of dirty needles dropped, while the number of people seeking treatment for drug addiction more than doubled.

Portugal's brave stand amounts to a decision to "Screw Business As Usual" -- the title of my latest book and a mantra that should be adopted by people holding positions in company boardrooms and government cabinets the world over.

4. Building for the future.
Virgin businesses have always emphasized the need to challenge the market and do things differently -- values we are keen to share with a new generation of entrepreneurs in the developing world. In 2011 we continued to expand our efforts, launching the new Branson Centre of Entrepreneurship in Jamaica and moving our center in Johannesburg to new premises, under a new CEO. Both centers are focused on helping young entrepreneurs to expand their businesses by offering practical advice and mentoring.

I brought groups of business people to South Africa and Jamaica to meet our entrepreneurs; as always, the visitors were bowled over by the young entrepreneurs' enthusiasm and passion for their work. We hope to expand our efforts further and to find financing and maybe obtain government help in scaling up these centers.

Our society's social, environmental and financial problems remain challenging and it looks like next year will be a tough one on many fronts. We will need to look for bold solutions, because change means opportunity. Whether you can effect small changes at the local level or try to push for sweeping cultural shifts in your industry or sector, 2012 -- now -- is the time to make a difference.

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