This sub-sector contains some ninteen inhabited solar systems, and the majority of the book is devoted to delivering an almost in-character 'travelogue' style guide to what is found there. Additional comments aimed at Referees and (to a lesser extent) players are found in grey boxed text throughout. Sequoyah sub-sector is part of the alternate Traveller universe setting of Clement Sector, although individual worlds or the whole sub-sector could be put anywhere you please in your own universe.
To start with, there is a map of the sub-sector, a list of UWPs for the inhabited systems and some general notes. As this alternate setting uses a Zimm Drive rather than regular Traveller Jump Drives (consider a Zimm Drive as roughly equivalent to Jump-2), comments include discussion of how far you can travel and how the systems in the sub-sector are grouped into 'regions' according to their accessibility.
Then each system is described in turn, beginning with an astronomical overview of the system describing all the planets within it before focussing down on the inhabited world which is probably the main focus of attention. Physical, atmospheric, hydrographical and geographical data set the scene, along with a planetary map, and this is followed by details of the population, government, laws, culture and notable cities. Other information is included as appropriate, especially noteworthy natural features, unusual customs or anything that a typical visitor might want to seek out.
There is a wide diversity of worlds both in natural details and in how they have been developed and run by human inhabitants. With the alternate setting being based on a fairly recent influx all the way from Earth (yes, the one you're sitting on reading this) through a wormhole which has now closed, many draw on fairly unadulterated heritages of wherever on Earth they came from, which makes for some interesting places and attitudes which yet have some familiarity to the reader. Even if you do not use this setting, it can make for an enjoyable visit although you may want to downplay some of the more overt references to each colony's origins. OK, so the folk on Bowemiwak may like barbeques and slow-roast pork, you just don't have to mention that they originated in Texas! In fact it can be quite fun NOT referencing the heritage, let the characters (or at least their players) deduce it for themselves.
The descriptions of different worlds spawn quite a few adventure ideas specific to that world as well as the more general ones involving exploration or trading. Some suggestions are also included in the grey box comments although they are mostly vague enough that it will not matter if players have read them - it's still up to the Referee to take the suggestion and detail an adventure around it.
It's a fascinating collection of worlds and visiting them makes for a splendid series of adventures. Whether or not you use the alternate universe, it is worth considing these worlds for inclusion in your game.