Only some people are done working at the end of the day; for some, job number two begins at night. That's where the name of Conen's research project Moonlight comes from. 'Research on people who also work through the evening and night out of financial necessity started in the United States. Economists called them 'Moonlighters,' Conen explains. It is 1 of 7 countries where Conen and her team study the well-being of so-called multiple job holders.

Growing group of people with multiple jobs

'Traditionally, research around the labor market has been about whether or not people have jobs. At one point, I noticed that self-employed people often combine work. This group has been growing for years. However, part-time salaried workers are also increasingly combining multiple jobs. This is related to how we organize work: it is becoming increasingly fragmented. Partly, this is their own choice, and partly, people are forced to organize their work this way. Now, we only know something about the well-being of people with one job. We can't say anything about the well-being of people with multiple jobs, even though that is now 10 percent of the population. What does that do to people? It's relevant for the future to know that.'

Why is it important to know more about the well-being of this group?

'If you know more about workers' well-being, you can also better ensure their well-being. I want to use the concept of total worker well-being as a benchmark. If you know what well-being is made up of, you can interpret it more easily.'

What do you mean by total worker well-being?

'That's a combination of different elements. For example, are you satisfied? Do you experience growth? Together, those elements determine your overall well-being. That concept still needs to be created for a work situation. In this project, I want to see what that's like for people with multiple jobs.'

It seems pretty complicated to determine people's well-being. How will you approach the research?

'In addition to a new large-scale survey data collection, we will develop an app to gather information. During the day, people in 7 different countries will occasionally be asked how they are doing. These are short ratings. For a year, they get these questions. Based on that, you can see how well-being is fluctuating and what's causing that. That's how we will get a lot of information. Eventually, we will also interview the people who have used the app personally.'

Do you expect the well-being of "moonlighters" to be better or worse than those with jobs?

'It depends. If you have a lot on your plate, are on a low income, and get little in return, it's debilitating. What happens to those people over a long period? On the other hand, it is enriching if you learn something in one job that you can use in another job. However, high-quality work can also have a negative effect if it is difficult to combine with work at home. I think a very mixed picture will emerge about people with multiple jobs.'

What would you like to see happen with the results?

'The findings can be used for practical measures. For vulnerable groups, you can better determine what combining jobs means for people. Based on that, you can organize more protection, for example. Employers can also respond better to it. You can all take measures and regulate things better, but first, you must know the bottlenecks.'