<p>Changing fields mid-career can be done (I’ve seen it done) but it can be somewhat problematic. Depends on how radial a change you are making. </p>
<p>You need to demonstrate to your new employer that you have the minimum skills to perform work in your new field. This may require additional classes. Do you go nights while doing your old job or full time and therefore have little or no income during that time?</p>
<p>You also won’t have the experience in your new field so you new employer will either have to overpay you or you will have to accept a pay cut to bring you in line with your skill level.</p>
<p>The people who I have seen that have done the best at a mid-career field change are ones that made small changes to their field of specialty.</p>