In the survey of more than 1,100 UK managers, nearly three quarters (73%) said their organisation was supportive of flexible working and 62% said they had senior managers acting as role models for working flexibly. The majority of managers (82%) also noted the business benefits that flexible working brought to the company.
The research also found half of managers (50%) believe flexible working is now standard practice where they work.
It also showed that men are just as likely as women to work flexibly, with 88% of male respondents currently working flexibly, compared to 90% of women.
However, a third (32%) of managers not working flexibly said they would like to, but are afraid to ask due to the culture in their organisation and a further quarter (27%) reported that it was not seen as appropriate for managers.
Charles Elvin, chief executive of the ILM, said: "Work used to be the place you turned up to - now, it's increasingly something you can do anywhere, at any time.
"This is because more and more employers are recognising that a flexible approach to how, where and when their employees work offers real business benefits, including increased staff engagement, reduced overheads and the ability to meet their customer needs more fully.
"Our research did identify a number of residual cultural barriers, which are preventing some organisations from fully embracing the advantages of flexible working. Negative attitudes towards flexible workers are often prompted by a sense of unfairness and poor communication from senior management on policy."
Elvin added: "Openness and honesty about flexible working policies can alleviate worries and uncertainty, help to address negativity and highlight the opportunities and advantages to all staff."