Generate an Acronym

R, 66 63 bytes

function(s)(s=substr(strsplit(s,' |-')[[1]],1,1))[s%in%LETTERS]

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-3 bytes thanks to Scarabee

An anonymous function; returns the acronym as a vector c("N","A","T","O") which is implicitly printed.

For once, this isn't too bad in R! splits on - or (space), takes the first element of each of those, and then returns whichever ones are capitals (LETTERS is an R builtin with the capital letters), in order.

V, 7 bytes

ÍÕü¼À!õ

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Here is a hexdump to prove the byte count:

00000000: cdd5 fcbc c021 f5                        .....!.

Explanation:

Í       " Search and replace all occurrences on all lines:
        " (Search for)
 Õ      "   A non-uppercase letter [^A-Z]
  ü     "   OR
      õ "   An uppercase letter
    À!  "   Not preceded by...
   ¼    "   A word-boundary
        " (implicitly) And replace it with:
        "   Nothing

This is short all thanks to V's wonderful regex compression.

Python 2, 59 56 bytes

^{-3 bytes thanks to Lynn}

lambda s:[b for a,b in zip(' '+s,s)if'@'<b<'['>a in' -']

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