This concept was devised by Mr. Daniel (Danny) Kleinman in the early 1960s. He was born March 13, 1937, in New York City, New York, United States. He presently resides in Los Angeles, California, United States. His occupations count singer-songwriter, writer, editor, professional bridge player, and also psephologist, which is a branch of political science which deals with the study and scientific analysis of elections. Also as an expert in the game of backgammon he has authored various books and publications about the game.

We thank Mr. Danny Kleinman for his contribution and also for his email explanation as for the necessity of modifying the Astro conventional method. His contribution is presented verbatim below for the benefit of the reader.

Short Biography

Mr. Daniel Kleinman is also a well-known backgammon player (profile) and author of numerous publications regarding the game of backgammon and also the game of bridge. Living in Los Angeles, California, United States he is a prolific bridge writer, theorist, professional player, and teacher, who is a regular contributor to several bridge magazines. He is a Contributing Editor of The Bridge World, and is one of the moderators of The Master Solvers' Club.

Note: The photograph below is from the year 2000.


Contribution by Mr. Danny Kleinman quoted:

From: Danny Kleinman
Subject: Kastro
Date: March 14, 2010

In 1961 or 1962, I learned ASTRO, named for its inventors Paul Allinger, Roger STern and Larry ROsler, the first Notrump Defense that was comprehensive (providing ways of intervening for all one-suiters and two-suiters): 2NT for minors, 2D for Spades and any other suit (including hearts), 2C for Hearts and a Minor. I played it with a regular partner, David Kitzes, and found a trouble sequence: 1NT-2D-pass-2H (neutral advance denying spades)-pass-2S (five Spades, with four or five cards in any other suit, perhaps four Hearts). Advancer then had to guess whether to bid 2NT to seek intervenor's other suit at the three-level, and a 4-4 or 5-4 heart fit would be missed from reasonable fear that intervenor's other suit was a Minor for which advancer lacked support.

To remedy this, I modified ASTRO so that 2C showed Hearts and another suit, possibly Spades, if the Spades were longer (or equally long but stronger). Then, with five Hearts and four Spades, intervenor would still bid 1NT-2D-pass-2H (neutral advance denying spades)-pass-pass, but with five Spade and four Hearts, intervenor would now bid 1NT-2C-pass-2D (neutral advance denying Hearts)-pass-2S (five spades)-pass-pass (intervenor's other suit is Hearts), and 1NT-2D-pass-2H-pass-2S now showed five Spades and a Minor (no longer a possibility that the other suit is Hearts). What to call this modification? KASTRO , of course, not only to add my initial to the initials of the ASTRO inventors but because in the early 1960s, many Americans feared and loathed a certain bearded Cuban revolutionist with a similar name.

Kastro Overcalls

This conventional defense method is employed after an opening of No Trump by the opponent and may be employed either in the immediate position or in the pass-out seat after two passes. This conventional defense method is a variation of the concepts Astro, Aspro, and Asptro, and employs so-called idle bids not employed in the original versions, which are shown below. Since there are so many idle bids in the original concept, variations have evolved. The version as designed by Mr. Danny Kleinman, called by him Kastro, is shown below.

Overcalls Following a No Trump Opening by Opponent

Double: Any double is for penalty. Partner must pass.
2 : Promises Hearts and another suit, possibly Spades if the Spades were longer (or equally long but stronger).
2 : Promises Spades and an unspecified Minor suit with longer Hearts.
2 : Promises Hearts.
2 : Promises Spades.
2 NT: Promises both Minor suits.
3 : A natural bid showing length in Clubs. Generally preemptive and obstructive in nature but with working values.
3 : A natural bid showing length in Diamonds. Generally preemptive and obstructive in nature but with working values.

The shape and distribution of the holding determines primarily the decision to make an overcall or not. The high card point count is secondary although the location of the values is a strong determining factor. The distribution is generally 5-4 by favorable vulnerability and should be 5-5 by unfavorable vulnerability when two suits are shown. Whether or not the principle concept can be employed with a distribution of 4-4 by any vulnerability is a matter of partnership agreement as are all continuances.



If you wish to include this feature, or any other feature, of the game of bridge in your partnership agreement, then please make certain that the concept is understood by both partners. Be aware whether or not the feature is alertable or not and whether an announcement should or must be made. Check with the governing body and/or the bridge district and/or the bridge unit prior to the game to establish the guidelines applied. Please include the particular feature on your convention card in order that your opponents are also aware of this feature during the bidding process, since this information must be made known to them according to the Laws of Duplicate Contract Bridge. We do not always include the procedure regarding Alerts and/or Announcements, since these regulations are changed and revised during time by the governing body. It is our intention only to present the information as concisely and as accurately as possible.