A student returning the reusable container after finishing her lunch. By changing the default from disposables to reusable materials, students changed their use habits. (Photo: UNDP)


As lifestyles change and a perpetual influx of single-use plastics are introduced in Honiara, the capital city of Solomon Islands, the city’s waste management system cannot keep up with the daily generated 80 tonnes of solid waste, of which 21 percent is plastics.

Residents of Honiara are well aware of the enormous challenge to manage these wastes, but so far, not much action has been taken to tackle the issue.

There are explanations for people’s actions and awareness of the trash problem. But there is also a difference between what people think and what they actually do.

To deal with this so-called intention-action gap, the United Nations Development Programme’s (UNDP) Waste Management Innovation Initiative supported by the Innovation Facility is employing behavioural insights. Behavioural insights draws on research in economics and psychology to understand how people actually behave in real-world contexts.

Behavioural insights, meet Pacific waste

Using behavioural insights to influence individual choices that serve the greater good is not new. But they haven’t been used to tackle solid waste management and single-use plastics issues in this way in the Pacific.

School lunches were served with single-use plastics before the intervention. (Photo: UNDP)

The initiative, with Behavioural Insights Team, has worked together to find solutions that prompt target behaviours related to reducing single-use plastics in an atypical context — school lunch service.

In Honiara, school lunches are often sold by parent vendors or school canteens, and they are almost always served with single-

use plastics such as the non-biodegradable Styrofoam, the hard-to-recycle plastic wrap, the cups made of polypropylene that dominates floating marine debris just to name a few.

The initiative has tested two different behavioural-insights informed interventions, which are a deposit-return scheme and a discount scheme.

It’s basically giving economic incentives to students who either bring back the re-washable food containers to the vendors after they finish their lunch, or bring their own food containers from home.

Testing in progress

The trial started in mid-July 2019 in five schools and was carried out for 13 weeks with approximately 75 vendors and more than 5,000 students involved. Data were collected on a weekly basis from the schools running the trial under their own leadership and circumstances, and many notewothy things happened.

At the preparation stage of the trial, UNDP consulted with each school to determine what type of reusable containers, plates or bowls suited their lunch and recess services and the schools were also involved in purchasing the items based on their decisions. Most schools gradually took ownership of the trial and convinced students, vendors and teachers to use the reusable items in order to adapt to the intervention applied to their lunch service.

For example, one of the schools displayed some posters on reducing single-use plastics to raise awareness of the students and vendors. Another school teacher requested vendors to bring foods in food warmers instead of pre-packaging them in single-use plastic containers, so that the vendors can serve the food in the re-washable stainless-steel bowls during the lunch break.

However, many vendors, especially those at the schools testing the deposit-return scheme, said raising the price of their food, paying back the deposit when students return the reusable bowls & containers, and washing them takes time and causes them to lose customers (and we don’t want that). The schools and the initiative team called on creativity to solve these issues together and continued with the testing process.

This is innovation        

The behavioural-insights-informed intervention is intended to influence the general public’s behaviour in a positive way to reduce the generation of plastic waste to help the government manage waste.

A student using a reusable container instead of a single-use plastic bag. (Photo: UDNP)


The streak of originality came in changing the common development approach of using awareness raising as a tool to change behaviour. With the intention-action gap in mind, the initiative applied the interventions to service providers within the schools to change the default away from single-use plastics. The lunch & recess vendors, canteens and schools, which have been providing the single-use plastics, became the conduit to reduce or eliminate them. By changing the default from disposable to reusable materials, and giving the students an alternative to using single-use plastics, the students started to change their use habits.

Beyond the initiative

Pilot data from the five participating schools will be analysed to help understand how this intervention can be best applied in other schools, to help reduce solid waste generation and improve its management in Honiara.

To cut down on plastics beyond what the interventions entail, we are encouraging schools to develop a school policy that limits or bans plastic bags, packaging and other single-use plastics.

UNDP is encouraging schools to develop a policy that limits or bans plastic bags, packaging and other single-use plastics. Behavior change takes time, and although schools are now using reusable containers, many still use plastic straws and cups. (Photo: UNDP)


The next phase of the initiative will replicate or scale up to other schools in Honiara and across the country. We will use the pilot results, lessons learned and feedback from the schools and key partners to fill gaps and inform the scale up.

The problem of the management of single-use plastic is growing globally, particularly in island and developing nations. Our evaluation will help understand what works to best address this problem through behavioural insights interventions, so that the findings can be applied in other contexts.

It’s all in the name of matching intentions with actions through applying behavioural insights to change the city and waste management for the better.

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