In recent months, social networking sites have been bombarded with videos of celebrities and the general public throwing buckets of ice water on themselves in the name of ALS (Amyotrophic Lateral Sclerosis) research. After an icy soaking, participants make a small online donation and nominate three people to undertake the challenge within 24 hours.

The perfect mix of social media, celebrity engagement and philanthropy – the Ice Bucket Challenge has become a viral phenomenon. According to Facebook, between the period of June 1 and August 17, over 28 million people commented on, or liked a post about the challenge and 2.4 million videos were shared across the site.

To date, the campaign has secured donations of over $31.5 million for ALS, compared to $1.9 million over the same time period last year.

Why has the campaign been so successful?

The idea of dumping ice water on your head in the name of charity is not new and until earlier this summer, it was not even associated specifically with ALS. So how did this movement go viral and raise so much money over such a short period of time? We have identified four key elements, which contributed to the unprecedented success of the campaign.

1. Timing

The Challenge got underway in June and peaked in August. The timing was perfect, as it took place in the heat of summer, (when everyone needs cooling down!) and during the vacation season, making it easier for people to spare the time to do take part. It was also a feel-good counterpoint to the images of violence in the Middle East that had been dominating the news.

2. Simplicity

The simplicity of the Ice Bucket Challenge made it accessible to anyone with a social media account and a mobile phone. The rules were so loosely defined that participants quickly engaged with the concept and adapted their own rules. For example, Charlie Sheen dumped a bucket of $10,000 onto his head instead of water, while Bill Gates built his own pulley system to complete his challenge, which generated nearly 17 million views on YouTube. The sense of ownership that individuals had over the campaign put a unique spin on each piece of content, which allowed for its share ability.

3. The "social currency" element

As the Ice Bucket Challenge started to gain momentum on social media sites, frequent users jumped on the bandwagon to show that they were part of the crowd – each of those people then nominated three other people to take part, and so on. The chain letter effect of the campaign meant that it went global almost immediately. 

The campaign also played on one of our strongest emotions – guilt. As nominations were made on camera and then posted online, they were visible to people’s wider social network, adding a social shaming element for those who choose not to participate.

4. Strong Call to Action

Issuing a challenge to others is more likely to inspire participation than merely suggesting that others partake. The “24 hour” plea is a vital factor in this - by giving people 24 hours to participate, it deters them from putting it off and forgetting about it.