English grammar - which of the two is correct:
1). "I must decide between one OR the other"
2). "I must decide between one AND the other"
...if both are correct, depending on the situation, please indicate so.
Need an explanation and actual reference to a reputable grammar source online.
Thanks,
Greg

Hi greg200-ga,

Although I was pretty sure of the answer, i.e. that "between ... AND"
was the correct or at least preferred usage, it was harder than I
thought it would be to find an online reference saying so. However,I
did finally locate two reputable sources for you that do state it
clearly, though it is also clear that, as bill10-ga implied in his
comment below, the difference is really a matter of style rather than
prescriptive rule.

In your example you are talking a decision involving a choice
involving two entities. BOTH of them are being considered, which is
indicated by using "between ... and." Using "or" doesn't work, because
that would mean you are considering only one, and of course we cannot
talk about deciding "between" only one entity. The word "between"
itself implies a plurality of two, though it can refer to more under
certain circumstances. The "American Heritage Book of English Usage,"
talks about this when it says that "between" is used when "entities
are seen as determining the limits or endpoints of a range." See here
for a more complete discussion:
http://www.bartleby.com/64/pages/page77.html

And so, in standard usage, "Between" should be followed by ... nouns
and/or pronouns joined by "and,"" although an example is given of
non-standard usage of "or" similar to your example above.
  --From an archived issue of Acu-Write, a free newsletter published
by Portico Books. See here:
http://www.grammarandmore.com/edu/acu-write.htm#f and scroll down to
the paragraph entitled "between/among."

"...note the correct use of between ... and in this sentence: They had
a choice between wide shoulders and sidewalks. Using between ... or
instead is incorrect: They had a choice between wide shoulders or
sidewalks."
  --From "Garbl's Editorial Style Manual," a free online style guide
based on the Associated Press Stylebook and other references:
http://home.comcast.net/~garbl/stylemanual/a.htm#among

The AP Stylebook itself is not available for free, but it is for
purchase, in print and online editions. If you're interested in
obtaining a copy, here's where you can find more information or place
an order: http://www.apstylebook.com/

By the way, I couldn't find anything about this particular use of
"between" in Strunk's "Elements of Style," but it's still a good
reference and it's available online at Bartleby.com for free. Here's
the link in case you'd like to have it:
http://www.bartleby.com/141/index.html 

I hope this fully answers your question, but if not please do use the
"Request Clarification" feature to ask before rating and closing your
question. I want to be sure you have what you need!

Thanks for an interesting hunt.

Best wishes,
Byrd-ga

Although, as I said, initially it was a challenge finding specific
information on this topic, ultimately the following search terms
yielded the best results:
[English grammar "between followed by"]
[English "correct use of between"]
[english usage "between"]

I also searched for "between" on Bartleby.com in the Reference section
under English Usage, Style and Composition, here:
http://www.bartleby.com/usage/

Byrd - thank you for such a well researched answer! This is excellent info.
Greg

In Microsoft Word 2003, type in the the sentence, "I must choose
between one or the other."  Then do a grammar check.  The
grammar-checker will pick up an error and direct you to change the
"or" to "and."  If you check "explain" in the dialog box, the follow
explanation will come up:
"If you are choosing 'between' to associate two items, join the two
with 'and.' It is incorrect to join them with 'or.'  Examples with
more explanations follow.  I hope this helps.

You could choose one or the other.
But you have to decide between one and the other.

Both are correct, but they have two different meanings.

With "and", you are suggesting a position, possibly in the middle. 
With "or", you are making a choice and eliminating one of the items
you're between.

If there are more than two items, use "among."

Don't trust Microsoft's grammar check.  It's often wrong.  Go to
Strunk and White's "Elements of Style."

I want to thank everyone for helping me with this question. Thank you very much!
Best,
Greg

Dear Greg,

You're most welcome, and thank you for the kind words and five stars!
I'm happy I was able to help, and that you're pleased!

Best regards,
Byrd