Getty ImagesMillions of people will be able to get sick pay from the first day they are ill and claim unpaid parental leave as soon as they start a job, in a major overhaul of workers' rights.
However, certain measures in the Employment Rights Bill have been criticised for being watered down or delayed.
Most of the planned changes will not take effect for two years following a period of consultation.
The government said the bill marked the "biggest upgrade to rights at work for a generation", but business groups are concerned about how the changes will work in practice.
Deputy Prime Minister Angela Rayner defended the time taken for changes to be introduced.
"Some things will take a little bit longer," she said, because of the scale of the reforms.
But she said many employers had already brought in some of the proposed changes.
The government is seeking to be pro-worker and pro-business and striking that balance means that much of the detail is still to be decided.
As part of the plans, the existing two-year qualifying period for protections from unfair dismissal will be removed.
Ministers have said this will benefit about nine million workers who have been with their current employer for less than two years.
However, workers will be subject to a proposed nine-month probation period when they can still be sacked without a full process.
If a worker is sacked within those nine months, it is unclear under what circumstances they can make a claim for unfair dismissal and when they cannot.
What else will change?Statutory sick pay (SSP): Workers will be entitled to SSP from the first day they are ill, rather than the fourth dayLower earnings limit for SSP: Currently, workers earning less than £123 per week cannot claim SSP. This limit will be removed but the bill will set out a lesser level of sick pay for lower earnersPaternity leave: Fathers or partners to be eligible from day one of employment, instead of 26 weeksUnpaid parental leave: Parents to be eligible from day one of employment, instead of one yearUnpaid bereavement leave: To become a "day one" right for workersFlexible working: Bosses will be expected to consider any flexible working requests made from day one, and say yes unless they can prove it is unreasonable. There are eight grounds they could give for refusing a request, relating to impact on the business
'Clumsy and chaotic'Many big business groups welcomed the plans, with the CBI saying the government deserved credit for engaging with employers and unions when working on the bill.
Ann Francke of the Chartered Management Institute, said that for many firms the proposed changes "won't create much of a challenge, as the government is in many cases just formalising practices that smart employers already follow".
However, while that may be the case for big businesses, smaller firms may be left "scrabbling to make sense" of the changes, according to Tina McKenzie, policy chair at the Federation of Small Businesses, whose members employ up to 250 workers.
She said the new bill was a "rushed job, clumsy, chaotic and poorly planned".