Torrune Merchants' Guild

The Merchants' Guild of Torrune is an association of all the city’s major merchants, dedicated to defending and advancing their own collective interests and protecting themselves against encroachment or outside competition. It also serves to represent the city’s merchants, as a collective body, to the court of the Archon and his Portreeve. Such guilds (for merchants as well as for other various sorts of tradesmen and artisans) exist in many towns throughout the Helvandrian League and beyond, but the Merchant’s Guild of Torrune is particularly large, wealthy, and influential. Since Torrune controls the crucial Helvander cataracts and the portage road around them, its merchants and their guild are the single most powerful player in the enormous (and enormously profitable) Helvander river trade. The power and influence of the Torrune Merchants' Guild is matched only by their counterparts in Hakoris, whose guild controls that city’s harbor and much of the lucrative sea trade that flows through it. 
The Merchant’s Guild exists for the merchants to advance their own interests, but also as a way for the Lord of the City (who has extensive mercantile concerns of his own) to monitor and regulate their activities. Everyone knows that the archon and his cronies use the institution of the guild to keep an eye on the city's biggest traders and monitor the political activities of the mercantile class. After all, the current archonal clan--the House of Gedeira--was itself just one of Torrune’s several wealthy merchant families before it managed to supplant the previous ruling household through canny political maneuvering. Every merchant who conducts trade in Torrune with a value exceeding a certain amount per year is not just permitted, but required, to take membership in the Guild (the threshold is such that all of the major merchants, and a handful of the most successful mid-tier ones, are included). Membership is conversely forbidden to those whose annual trade is less than the threshold, although many of these middle-tier and small-scale merchants voluntarily organize themselves into their own, much less important, trade guilds.
Guild members (often simply called called guilders) pay annual dues and swear reciprocal oaths to support and aid each other, to uphold their mutual interests, and to cooperate against any threat to their shared dominance of the Helvander river trade. In this sense, the guild is a sort of cartel, or a mercantile union aimed at upholding a shared monopoly. But of course the major trading houses of the guilders are all in competition with each other as well. In this way, the Guild resembles the Helvandrian League itself in miniature: Its members cooperate to present a united front to any outside challengers, but simultaneously vie among themselves for primacy, and each would be glad to marginalize the others and take the lion’s share for himself if he could. 
The Guild also fulfills certain functions of a bank for its members, including taking deposit of valuables for safekeeping, and making loans and issuing promissory notes, bills of exchange, and so forth. For various reasons, the merchants may sometimes prefer to handle such business through their own guild rather than with the priestesses of Sidra or other outside brokers. The Guild sometimes agrees to provide such services to non-members as well, although of course they charge additional fees in those cases.
Although the guild and its members are regulated by the archon’s law in various ways, they are also granted the right to make their own rules on certain matters concerning trade in Torrune. For example, the archon’s own law governs the movement of trade goods in and out of the city (especially, of course, the inspection and taxation thereof), but the guild is granted the right to regulate the quality, prices, etc. of all manner of goods sold within the city. Olive oil, wine, wool, ale, spices, metalwares, and numerous other products are subject to this regulation by the guild; for instance, they might impose a rule that wine categorized as first-rate quality cannot be sold for less than ten gold XXXXXXes [Helvandrian coin] per barrel, wine graded second-rate quality cannot be sold for less than four XXXXXes, and so on. The ability to set these rules gives the guild all manner of ways to benefit its own members commercially. 
Members of the guild and their families are exempted from certain city taxes and obligations (as well as all corporal punishments, except death) and cannot be obligated to bear arms in service of the archon. They have all manner of special rights, prerogatives, and privileges as befits their high status. The exemption from certain taxes is premised on the idea that, as major traders, the fees and tariffs they pay on their goods coming through the city already make an ample enough contribution to the archon’s coffers. Their exemptions include some taxes that would otherwise be levied on businesses and property holdings within the city, so there are ample benefits to guild membership which offset the fees and other obligations. 
The Guild also performs various civic and charitable functions such as alms-giving and feeding the poor, donating to the city's temples, and putting on pageants, banquets, and other celebratory events at the major holy days. In addition, they put on their own festivals several times a year. Their guildhalls are often opened to the public as venues for these celebrations and feasts (the courtyards and outer or lower halls for the common folk, of course, and the grand chambers of the high halls for the well-to-do and connected). The Guild also organizes and funds civic activities such as cleaning the streets, removing rubbish, providing night-watchmen, and hanging lamps along the lanes at night. Naturally these activities tend to be focused on the city's wealthy and middle-class neighborhoods; the poor districts of the Low City are passed over. 
The head of the Merchants' Guild, called the Guildmaster, is periodically elected by its membership (with votes awarded in proportion to each member's wealth) and serves as the principal of the Guild Council (likewise elected from the membership, with requirements of wealth and seniority to stand for the seats). The current Guildmaster is Arevallo of the House of Othul. The Guild's official business is mostly conducted from the New Guildhall in the Low City, whereas its ceremonial and celebratory functions are held at the Old Guildhall in the High City.