Hi Walter!
My opinion is that it's not always required. However depending on the job you're looking to apply for, the knowledge and skills required to be hired can be based on what is taught in computer science such as algorithms, data structures, architectural design, etc.
For those without a degree in CS, I'd recommend learning these concepts and practicing them in code. These fundamental skills help you write better software, and you'll find it easier to take apart existing software and articulate how it's put together. This can in some circumstances help your profile and performance in technical job interviews.
I and many other colleagues/friends of mine working at Microsoft and other large companies (such as Google, Facebook, etc) do not hold computer science degrees.