Expanding into other development sectors

[tgrt]

How would one go about expanding their knowledge into another development sector? I have been in the manufacturing sector for my entire career; and I have recently become interested in the healthcare sector. I'm not necessarily looking to change my current focus, but I'd like to learn more and maybe dabble a little for fun and profit. For any sector-focused developer there is a certain degree of domain expertise needed, so that may be the main issue.