I'll tell you what I usually do.
Whenever designing a new brand I choose my colours from a pantone book. This is because it is the tools I found colour was actually accurate. After this I go online and some websites give you the correspondence of that particular pantone in CMYK and RGB.
This is the website with an example:
This has worked just fine for me.
Just don't forget to include on your band guidelines a shape with pantone and one with CMYK and RGB. This is because every time you send something to print some machines may not read the pantone reference. (I am assuming you will work in illustrator).
Last but not least always always give the production company your pantone reference and ask for proof of colours because that way you will be able to avoid nasty suprises.
So basically, it is not exactly different colour palettes but different colour values. And you should always have CMYK values and RGB values on your brand guideline documents along side the pantone you chose.
Also it will happen in illustrator that when you have a document in CMYK mode and insert RGB values they will change slightly once you change the document to RGB.
If say you are going to save a logo for RGB use make sure you have the correct colour mode set before you tell illustrator the colour values.