The Bid Of Three Spades
The bid of three Spades when made by the Second Hand shows a holding of
at least five (probably six) Spades, almost certainly without the Ace
and probably without the King, but with some side strength. It says, "I
want this hand played with Royals as the Trump, but I cannot bid that
suit now, as I have not the requisite high-card holding. Either because
the rest of my hand is so strong that I fear neither the Third Hand nor
my partner can bid, or for some other good reason, I prefer now, rather
than later, to give my partner all possible information."
 See page 123 as to how the partner should treat this
This system of bidding differentiates most accurately between the
various lengths of Spade holdings and enables the partner to elect
between No-trump and Royals, with an exact knowledge of the situation
not otherwise obtainable.
Next: How Second Hand Should Bid After An Offensive Declaration
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