In fact, there is more to answering this question than meets the eye. As someone who’s also been skeptical enough to do the research, I am more than happy to explore the issue in great depth. The important thing to address here is what have you been told that Brainwave Entrainment would do?  Depending on whose site you’ve landed on you may have been promised different things.  The promised benefits of this type of product are a long list, and more things are still being added to it.  You may have been told that brainwave entrainment would help you meditate deeper, and rocket launch your spiritual evolution from doing so.  You may have been told that it would help your brain release positive neuro chemicals and anti-aging hormones that would improve your health and help you feel more positive emotions, overcoming anxiety, and you also may have been told that listening to brainwave entrainment on a regular basis would help your brain evolve, building a higher threshold to mental and emotional input, growing neural pathways, and synchronising the two hemispheres of the brain.

Deep relaxation is a major benefit resulting from the brain’s cortical frequency following response. By selecting the desired rate the brain, via the frequency following response, will tend to mimic the rate it is exposed to and thus enter that brainwave state. This helps to explain why this technology can produce benefits commonly found with meditation. One of the most valuable benefits of consistent  brainwave entrainment is that we are able to experience and recognize the various states of consciousness. With practice we can learn how to re-create these states.
Neural oscillations are rhythmic or repetitive electrochemical activity in the brain and central nervous system. Such oscillations can be characterized by their frequency, amplitude and phase. Neural tissue can generate oscillatory activity driven by mechanisms within individual neurons, as well as by interactions between them. They may also adjust frequency to synchronize with the periodic vibration of external acoustic or visual stimuli.[3]