The GURPS rules are flexible in multiple ways.

1. The GURPS rules are generic.

The game rules include a relatively simple, generic core which remains compatible with the addition of increasingly more detailed, but optional, rules.

Such optional rules often are added for the sake of increasing the game's sense of realism (in the sense of real-world simulation). Using a minimum of general, core rules, a given group may opt to play a game that's simple and fast-moving.

Alternatively, a group may include an abundance of optional, but more detailed rules, achieving an intensified sense of realism - but also playing a game with a slower pace.

By combining the generic core and a moderate number of optional rules, a given gaming group can strike its own, preferred balance between speed and ease of play on the one hand, and a sense of realism, on the other, choosing with what aspects to emphasize realism and with what aspects to emphasize speed of play.

This generic quality of the core rules is one aspect that enables GURPS to function as an expandable, yet integrated, system. (The systematic nature of GURPS is explored as part of point 5, below.)

2. GURPS is universal. The game rules provide a universal platform on the basis of which to play. The rules do so in at least four, distinguishable ways.

a. The game rules welcome the adaptation or creation of virtually any imaginable adventuring environment - whether fantasy or historical; past, present or future. Thus, the rules universally facilitate the use of any adventure setting or world.

b. Similarly, the game rules welcome the adaptation or creation and roleplaying of virtually any imaginable character. Thus, by facilitating the adventuring of any variety of character, the rules are likewise universal.

c. By encouraging the optional use of virtually any role-playing game supplements or source books - whether they were specifically designed for use with GURPS or with other games - the GURPS rules are universal in a third sense.

d. By equally encouraging the optional use of virtually any source material, whether historical or fictional, and whether in the form of books, magazines, television, movies or virtually any other medium - the rules are universal in yet a fourth sense.

3. GURPS enables and encourages satisfying role-play.

By employing a point system for the purposes of character creation and development, the game rules encourage both imaginative character creation and satisfying role-play.

4. GURPS enables and encourages satisfying role-play.

The rules emphasize that whatever details or optional rules are used, the object of the game is to have fun. In this respect, the rules encourage satisfying role-play.

5. GURPS establishes a standard for expanding a given group's adventure gaming systematically. This is so in at least, three senses.

a. By providing a simple, generic core onto which however many more detailed rules optionally may be added, the rules facilitate systematic expansion. (The generic nature of the game's rules is explored more in point 1, above.) Even the optional rules range from the relatively simple to the highly detailed, and as few or as many may be added while still preserving the game's systematic integrity. In this sense, the rules are designed to function with one another as a unified whole, rather than as a contradictory patch work.

b. Steve Jackson Games ensures that GURPS-branded material maintains what in their judgment qualifies as a high standard of quality and such material remains consistent with the core rules. Using such material, a given group can expand its adventure gaming in a way that's thoroughly consistent, systematic and integrated.

c. By emphasizing a foundation of realism (in the sense of real-world simulation), the rules welcome the systematic incorporation of practically any other source material - even material that was never intended for use with GURPS. The rules do so in at least two, distinguishable ways.

i. The rules feature such real-world units of measure such as feet, yards and miles, which help to facilitate the adaptation of material from games, books and other sources.

ii. Perhaps ironically, this foundation in realism also facilitates the adaptation of fantastic settings, situations and characters. Only those things that differ in a given fantasy need to be changed, while the rest can be left alone.

Note

¹The word GURPS is a trademark of Steve Jackson Games. In writing the foregoing commentary about GURPS, in my opinion, I've benefited from inspiration that I drew from such rules sources as GURPS Basic Set: Characters and GURPS Lite. Even so, the definition and elaboration that I'm offering here are my own. Please note that I don't assume that Steve Jackson Games would necessarily agree with my formulations.