Last month, David Blunkett delivered both the good and bad news on charitable giving in the UK.

In his introduction to the 2014 Charity Aid Foundation's report Growing Giving report (pdf), he affirmed that interest and passion for charitable causes from people of all ages is alive and well in the UK. We are still the sixth most generous nation on the planet.

The bad news is that giving isn't growing. According to the report, the percentage of adults giving to charity is stuck at around 57%, 2% below the level achieved before the economic crash. More importantly, we are becoming overly dependent on an older cohort of donors who make up just 9% of the population but provide over 60% of charitable income. This reliance on a 'civic core' is not new but still should be a concern for every fundraising director in the UK.

At Voluntary Service Overseas (VSO), we are taking two important steps to mitigate against these risks. First, we recognise that in keeping with the trends of an ageing civic core, our own supporters and returned volunteers are getting older. We know there has never been a more important time to promote and maximise giving through legacies. We also know that we are working from a low base, in part due to a misconception in the public's mind that VSO is an arm of government rather than an independent charity. Legacy income only provides just over 1% of our global income. This is despite the fact that in the UK legacy income is worth over £2bn and makes up 13% of all money given to charities. We realised we should be doing better.

So, in 2011, VSO developed a global fundraising strategy in which we decided to invest in our first legacy manager and increase our legacy marketing budget. Our legacy income over the past three years has grown steadily but we know that is not necessarily a result of the increased investment. It is too early to tell how current activity and investment will affect our future income. Our rule of thumb is that activity undertaken today will only have a positive impact on income in a minimum of six years (the average time between when someone last updates their will and passes away). However, the signs look good. We can see there is a growing number of legacy pledgers and a healthy proportion (32%) are former volunteers which increases our confidence that there is healthy future growth in legacy income for VSO.

We also needed a more immediate response to find the new donors on which we could build a sustainable future. The recruitment of donors is becoming increasingly competitive but the key for us was finding a channel that suited our brand and proposition to recruit more donors. There has been no substitute to testing a variety of approaches from TV to digital, and door-to-door mailing. We have seen that people have connected with a proposition to enable real people, and volunteers at that, to support communities to overcome poverty.

Particularly through door-to-door, we have been able distinguish ourselves in a context of a one-to-one conversation. We also found that on average, the age of the donors we were recruiting was 47, far younger than our existing supporters. Most critically though, we saw that our offer had the potential to build donor loyalty – the promised land for any charity.

VSO donors are given the opportunity to receive firsthand accounts of the real impact our volunteers were making in country and vicariously participate in their adventure. One of our volunteers recently reported how she had to beat off a cobra in her backyard which seemed to delight and surprise donors in equal measure.

Over the last year, income from legacies in the UK has grown by 75%. VSO's overall income rose from £57 million to £68.7million – an increase of 20%. Crucially, this growth has only been possible through strengthening the capacity of the functions around fundraising such as our database team, our story-gathering team and our media and PR team.

We are still on a learning curve but our experience bears out that growth in this market is possible. You do need a board willing to approve investment and clarity over the right mix of routes for your proposition to achieve growth. We are hoping that leads to more good news in the years ahead.

Editor's note: do you work in NGO fundraising? Share your challenges and achievements below.

Mark Rowland is head of fundraising and partnerships at VSO UK. Follow @VSOUK on Twitter.

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