Telephone ringing? Baby crying? Partner snoring?
If you're constantly being woken by noise, the trick to getting a better night's sleep may be to fight noise with more noise - specifically, the sound of 'white noise'.
Scientists know that even when we are sleeping our brains process noise - so a sudden change in sound or volume can take wake you up.
See also: Top tips for getting a good night's sleep as you get older
So rather than trying to create a silent environment, it might be easier to switch on some 'white noise' to help mask other sounds.
'White noise' is a consistent non-repetitive sound that doesn't create an emotional response in the listener. Natural sounds like a waterfall, mechanical sounds like a running air conditioner or washing machine are all types of 'white noise'.
Studies have shown that the benefits of sleeping with 'white noise' include more hours of restful sleep. It can also have a soothing effect on babies and increase concentration.
Try 30 minutes of 'white noise' for relaxation. It's easy to find online - from smartphone apps to online videos.