The House of Lords science and technology committee has spent the last few weeks gathering evidence on the effect EU membership has on British scientific research.
Members have spoken to scientists, industry leaders, charities, government ministers, and others in an attempt to get a full picture.
And in a major new report, they found that by an "overwhelming balance of opinion", the British science community "greatly valued the UK's membership of the European Union".
The report gave various reasons for that. One major one was funding. Britain does extremely well out of the EU's science budget.
Britain pays in about £5.4 billion a year towards EU science and receives £8.8 billion in return. Only Germany receives more from the main EU research funding pot.
The report said that "science and research are a significant dimension of the UK's membership of the EU".
Another was that freedom of movement within the EU means scientists can easily move between countries and recruit researchers from elsewhere. The report said this was "vital".
If you're a citizen of an EU member state, you are allowed to live and work in any other EU country without a work permit.
Academics said this allowed them to recruit the best talent from overseas; they also said it meant British scientists were able to go and learn new skills from specialist institutes abroad.
The report found a "very strong consensus" that researchers being allowed to move freely between EU countries was good for British science. It concluded that "researcher mobility must be protected if UK science and research is to be world-leading". It also noted that government immigration policy for non-EU countries was having a "negative impact" on science recruitment.
Having standard regulations for research across the EU was also broadly seen as a good thing.
Sometimes EU regulation got in the way of scientific research, but in general, everyone having to abide by the same standards was helpful, the report found.
Jurgen Maier, CEO of Siemens UK, told the committee that "trying to get 28 countries to achieve a common standard … is going to be difficult, but when you have achieved it, it makes processes and design and manufacture a lot simpler."
Being a member of the EU also gives Britain more influence on policy, the report said.
Committee member Baroness Morgan of Huyton said in a briefing that "having a seat around the top table when decisions are taken, often the leading seat at the table", gives Britain a strong voice in directing EU science policy and funding.
The report concluded that the UK "plays a leading role" in the development of EU science policy, and said being a member of the EU gave the UK more weight in "scientific diplomacy" internationally.
It highlighted the recent climate talks in Paris, quoting scientists who said negotiating as part of the EU gave Britain "considerably more clout".
It also found that being a member of the EU makes scientific collaboration easier.
That's partly because of freedom of movement, but also because there are specific EU funding schemes for collaborative research, and because the EU fosters big international projects, several of which are based in Britain.
Scientists also told the committee that being part of the EU made it easier to collaborate with non-EU countries. Robin Grimes, chief scientific adviser to the Foreign Office, said "we work with the EU in China to maximise our policy impact … [EU membership] really complements our bilateral activities."
It found that EU membership caused some problems for EU science, however. One of the most prominent was regulation of research.
EU regulations on animal research, genetically modified organisms, and the sharing of medical data all have negative impacts on British research, the committee found.
The charity Sense About Science said "the expensive and complex regulatory system is a battier to the conduct of research on GM food", while Dr David Hughes of Syngenta described regulatory systems governing biotechnologies as "non-scientific, scientifically unjustifiable and dysfunctional … a bit of a mess".
The committee did say, however, that Britain played an important role in mitigating the worst effects of "inappropriate" regulation.
Another was the complexity of the funding system.
The report said that although Britain did well out of the EU's science budget, "UK researchers can struggle to navigate through the system" because it is unnecessarily complicated.
It also found that while academic research did well out of the EU, the picture was less clear for industry.
That was partly because of a lack of evidence, the report said, but also because British businesses received less money from the EU for research – below the EU average.
Overall, the committee was worried that Britain leaving the EU would lead to a drop in British science funding and a loss of influence on EU science policy.
They point to the example of Switzerland, which is an "associated country" rather than a member of the EU. It is still a "world-renowned" scientific nation, the report said. But since it voted in a referendum to curtail freedom of movement, it has been cut off from some sources of EU science funding.