Labour has renewed calls for a "cradle-to-grave" National Education Service, after a "catastrophic fall" in adult learners.
Shadow education minister Gordon Marsden has called for action, saying government cuts have led to fewer adults choosing to study later in life.
Labour says millions of adults in the UK lack basic skills and are unable to access education and training.
The government says further education and skills is a priority.
Labour's says its Nation Education Service - a 2017 manifesto pledge - would be "free at the point of use" and "open to all regardless of age, background or circumstance".
A learner-centred system could help reverse the decline in adult learning, according to the party's Lifelong Learning Commission.
The commission's interim report says that "lifelong learning should ensure that all individuals can access the high-quality education and training they need throughout their lives, to improve their lives and their life chances".
The report quotes 2018 figures from the Institute for Fiscal Studies, suggesting that funding for adult learning and apprenticeships has fallen by 45% in real terms since 2009-10.
"Lifelong learning is about social justice and personal empowerment," Mr Marsden said, as well as the reskilling the "country desperately needs".
Decline with age
The government says that despite the range of learning and training opportunities currently available, the number of adult learners continues to fall.
Participation in government-funded adult further education fell by 3.5% in the first two quarters of 2018/19 on last year's equivalent figures.
The Department for Education has recently begun the rollout of a National Retraining Scheme, which it hopes will help adults whose jobs are at risk.
The £100m programme, currently being trialled in Liverpool, is meant to prepare workers who could be replaced by automation.
Research from the programme suggests that cost, employment working patterns and poor previous experience of education all act as barriers to retraining.
Earlier this year, a government commissioned review of post-18 education published its findings.
Among the recommendations was the introduction of a lifelong learning loan allowance, which could be used at any stage of an adult's career for full and part-time students.
Previous government research shows that participation in formal learning declines with age, and adult learning is "disproportionately" taken up by those who are wealthier and highly skilled.
Whether it's warnings of artificial intelligence taking jobs, or worries about skills shortages after Brexit, there are huge demands for adults to be able to keep on training and learning new skills.
But as this report from Labour points out, adult education - or "lifelong learning" - has struggled with being "disjointed" and often underfunded.
If your industry is in decline, or you're out of work, how would you go about re-training and getting the skills for a future-proofed job? It's not particularly obvious.
Compared with well-signposted pathways through academic exams - adult education can seem more of a maze than a route map.
At university level, mature and part-time student numbers collapsed when tuition fees were increased and have never really recovered. Further education has been among the hardest hit with funding shortages.
Labour will say the answer is in its plans for a National Education Service. But details remain sketchy and critics would say that it's a wrapper around an absence of policies.
Everyone agrees that adult education needs to be re-energised - but without the lobbying power of schools and universities, it will need a great deal of political backing to really raise its status.