Citysmith is a multi-player game -- designed to be playable by email -- the object of which is to be the first Player to construct and operate a complete City for one full round of play.

Structures
A complete City must include at least one example of all six types of City Structure:
Housing	Each City must have sufficient housing to provide labor to operate all its other Structures (exception: no housing is required to operate a Bank.) Each basic non-housing Structure requires one Housing Structure in order to operate and each Improved non-housing Structure requires two Housing Structures (or one IMPROVED Housing Structure -- which Houses two Labor Units) to operate.
Factories	Each operating basic Factory Structure produces one additional Action per Turn. Each IMPROVED Factory Structure produces two addtional Actions per Turn.
Offices	You must construct one Office unit for every two operating Factory units (i.e.--one basic Office Structure will permit you to operate two basic Factory Structures or one IMPROVED Factory Structure.)
Markets	At least one Market Structure is required in order to win a game of Citysmith.
Banks	A Player must have in operation one Factory, Office and Market Structure for each Bank he/she constructs. Instead of using it on the Turn he/she generates it, he/she may then Save one Action in each basic Bank Structure (or two Actions in each IMPROVED Bank Structure) and may withdraw those Saved Actions for use on any subsequent Turn.
Entertainment	At least one Entertainment Structure is required in order to win a game of Citysmith. In addition, unless a Player has one basic Entertainment Structure for every two Labor Units over the number needed to operate his/her Factories, Offices and Markets, he/she loses the extra Labor Units and their Housing.
Optional Rule for Defensive Bases:
Defensive Base	Each Defensive Base DEFENDS against one ATTACK from each opposing Player. Bases are not required in order to win. Each Base requires one unit of Housing to operate. Bases cannot be IMPROVED or REINFORCED.

Actions
Each round of play, each Player in Turn will take one or more Actions. Citysmith Actions include:
BUILD	A Player may BUILD a basic Structure.
REINFORCE	A REINFORCED Structure is not affected by QUAKES.
IMPROVE	IMPROVING a basic Structure doubles its capacity or production. A basic Structure that has been REINFORCED loses its REINFORCEMENT when it is IMPROVED, but the Player may use a subsequent Action to REINFORCE the IMPROVED Structure.
ATTACK	ATTACK another Player by announcing which of his/her Structures you will target. ATTACKING a basic Structure destroys it. ATTACKING an IMPROVED Structure reduces it to a basic Structure.
DEFEND	The Player must announce which Structure he/she is DEFENDING from ATTACK. That Structure is then DEFENDED for one Round.
PASS	Once a Player PASSES, he/she may take no further Actions that Turn.
SABOTAGE	Each SABOTAGE deprives the Player you target of one Action on his/her next Turn.
QUAKE	A QUAKE affects all Players. It destroys ALL un-REINFORCED Structures.
SURRENDER	The Player to whom you SURRENDER gains all of your Structures.

Playing Citysmith:

Use any method you like to choose a starting Player. Beginning with that Player and proceeding clockwise, (or in the order you've established ahead of time for email games,) each Player takes a single Action. (Since you must have a labor force in order to construct and operate your City -- or perform any Action except BUILD, PASS or SURRENDER -- everyone will likely choose to BUILD Housing on his/her first Turn.) The Round is completed once everyone has taken a Turn.

Play proceeds in this fashion until one Player wins by constructing and operating all six City Structures for one full Round. The winner becomes the starting Player for the next game.

Notation:

Citysmith is designed to be played by email, although it can also be played face-to-face, using a paper and pencil. Citysmith notation makes this easy. Basic Structures are represented by lower-case letters and IMPROVED Structures by upper-case letters. Pairing a lower-case letter "r" with a Structure shows it has been REINFORCED. Likewise, if you have insufficient Labor units to operate all your Factories, Offices, Markets and/or Entertainment Structures, designate operating Structures by placing a plus sign (+) next to them, or by placing a minus sign (-) next to IMPROVED Structures that are operating at half-capacity. Thus, the string "rH h F+ ro+ m" represents one REINFORCED IMPROVED Housing Structure, one basic Housing Structure, one operating IMPROVED Factory Structure, one operating REINFORCED basic Office Structure and one non-operating basic Market Structure. The notation for basic and IMPROVED Structures is:

hH	Housing
fF	Factory
oO	Office
mM	Market
bB	Bank
eE	Entertainment
and, optionally
g	Defensive Base

Example game:

The Players are Bill, Jim and Sue, in that order. Here are the first 20 moves of their game.

Round 1

Bill: BUILD Housing (h)
Jim:  BUILD Housing (h)
Sue:  BUILD Housing (h)

Round 2

Bill: BUILD Factory (h f)
Jim:  BUILD Factory (h f)
Sue:  REINFORCE Housing (rh)

Round 3

Bill: REINFORCE Housing (rh f)
      REINFORCE Factory (rh rf)
Jim:  IMPROVE Housing (H f)
      BUILD Office (H f o)
Sue:  QUAKE (rh)

Round 4

Bill: BUILD Office (rh rf+ o)
      IMPROVE Housing (H rf o)
Jim:  BUILD Housing (h)
Sue:  QUAKE (rh)

Round 5

Bill: BUILD Housing (h rf)
Jim:  BUILD Housing (h)
Sue:  BUILD Factory (rh f)

Round 6

Bill: REINFORCE Housing (rh rf)
      QUAKE (rh rf)
Jim:  BUILD Housing (h)
Sue:  ATTACK Bill's factory (rh)

Round 7

Bill: ATTACK Sue's Housing (rh)
Jim:  BUILD Factory (h f)
Sue:  BUILD Housing (h)

Round 8

Bill: BUILD Factory (rh f)
Jim:  REINFORCE Housing (rh f)
Sue:  BUILD Factory (h f)

Round 9

Bill: REINFORCE Factory (rh rf)
      BUILD Housing (rh h rf)
Jim:  REINFORCE Factory (rh rf)
      BUILD Housing (rh h rf)
Sue:  REINFORCE Housing (rh f)
      REINFORCE Factory (rh rf)

Round 10

Bill: REINFORCE Housing (rh rh rf)
      BUILD Office (rh rh rf o)
Jim:  BUILD Office (rh h rf o)
      IMPROVE HOUSING (rh H rf o)
Sue:  QUAKE (rh rf)
      BUILD Housing (rh h rf)

Round 11

Bill: BUILD Office (rh rh rf o)
      REINFORCE Office (rh rh rf ro)
Jim:  QUAKE (rh rf)
      BUILD Housing (rh h rf)
Sue:  BUILD Housing (rh h rf)
      REINFORCE Housing (rh rh rf)

Round 12

Bill: IMPROVE Housing (H rh rf ro)
      REINFORCE Housing (rH rh rf ro)
Jim:  REINFORCE Housing (rh rh rf o)
      REINFORCE Office (rh rh rf ro)
Sue:  BUILD Office (rh rh rf o)
      REINFORCE Office (rh rh rf ro)

Round 13

Bill: IMPROVE Factory (H rh F ro)
      REINFORCE Housing (rH rh F ro)
      REINFORCE Factory (rH rh rF ro)
Jim:  ATTACK Bill's IMPROVED Housing (rh rh rf ro)
      ATTACK Bill's Factory (rh rh rf ro)
Sue:  ATTACK Bill's Housing (rh rh rf ro)
      ATTACK Bill's Office (rh rh rf ro)

Round 14

Bill: BUILD Housing (rh h rf)
      REINFORCE Housing (rh rh rf)
Jim:  BUILD Housing (rh rh h rf ro)
      REINFORCE Housing (rh rh rh rf ro)
Sue:  ATTACK Jim's Housing (rh rh rf ro)
      ATTACK Jim's Office (rh rh rf ro)

Round 15

Bill: BUILD Office (rh rh rf o)
      REINFORCE Office (rh rh rf ro)
Jim:  ATTACK Sue's Factory (rh rh rf)
      ATTACK Sue's Housing (rh rh rf)
Sue:  BUILD Factory (rh f+ ro)
      REINFORCE Factory (rh rf+ ro)

Round 16

Bill: BUILD Housing (rh rh h rf ro)
      REINFORCE Housing (rh rh rh rf ro)
Jim:  BUILD Office (rh rh rf o)
      REINFORCE Office (rh rh rf ro)
Sue:  BUILD Housing (rh h rf ro)
      REINFORCE Housing (rh rh rf ro)

Round 17

Bill: IMPROVE Factory (rh rh rh F ro)
      REINFORCE Factory (rh rh rh rF ro)
      SABOTAGE Sue (rh rh rh rF ro)
Jim:  IMPROVE Housing (H rh rf ro)
      REINFORCE Housing (rH rh rf ro)
Sue:  BUILD Housing (h rh rh rf ro)

Round 18

Bill: IMPROVE Housing (H rh rh rF ro)
      REINFORCE Housing (rH rh rh rF ro)
      ATTACK Jim's IMPROVED Housing (rH rh rh rF ro)
Jim:  ATTACK Bill's IMPROVED Housing (rh rh rf ro)
      ATTACK Bill's Housing (rh rh rf ro)
Sue:  IMPROVE Factory (h rh rh F ro)
      REINFORCE Housing (rh rh rh F ro)
      REINFORCE Factory (rh rh rh rF ro)

Round 19

Bill: BUILD Housing (h rh rh rF ro)
      IMPROVE Housing (H rh rh rF ro)
      REINFORCE Housing (rH rh rh rF ro)
Jim:  IMPROVE Housing (H rh rf ro)
      REINFORCE Housing (rH rh rf ro)
Sue:  IMPROVE Housing (H rh rh rF ro)
      REINFORCE Housing (rH rh rh rF ro)
      DEFEND IMPROVED Housing (rH rh rh rF ro)

Round 20

Bill: IMPROVE Office (rH rh rh rF O)
      REINFORCE Office (rH rh rh rF rO)
      DEFEND Factory (rH rh rh rF rO)
Jim:  IMPROVE Factory (rH rh F ro)
      REINFORCE Factory (rH rh rF ro)
      DEFEND Factory (rH rh rF ro)
Sue:  IMPROVE Office (rH rh rh rF O)
      REINFORCE Office (rH rh rh rF rO)
      BUILD Housing (rH rh rh h rF rO)

Sue, who started out substantially behind, is about to take the lead -- unless one of her opponents ATTACKS. It's safe to predict that, on her next Turn, she will start by BUILDING a Factory, then IMPROVE her new Housing Structure, IMPROVE her new Factory and then REINFORCE both Structures, since putting a new IMPROVED Factory into operation will take her up to FIVE actions per Turn!