Nocturnal Wanderings

Aronburg is the glowing cap of the expanding civilization of the Lower Aron Valley, but it hasn't been able to completely remove its seedy and unruly underside. It has gradually become a much safer and more predictably stable community. The town leaders have gone to great lengths to clean up the streets and crack down on criminal activity. They have created a town guard force and begun construction of a constabulary near the ridge at the edge of town. So far, the majority of change has been cosmetic, but with the cleaner look, a certain pride has awoken within the townsfolk so that they have toned down their wild ways to a low simmer.
The reality is that the town decided to protect and enhance their business interests, and brought in a town guard to begin the process. Any success they've found is due to their collective interest in the effort working. There are still flare-ups, but it is becoming a regular town, not a frontier wasteland. Unfortunately, as the town develops more organization and discipline, the criminal elements have also begun to get more organized. What had been random mobs and scuffles is becoming more structured.
The weird aspect of this is that as the criminals have gotten themselves organized, the volume of violence and disorder has shrunk to nothing, appearing to have made the town safer as certain threats have grown. The criminal groups are still in their infancy, so that at least 5 or 6 significant ones hold sway on the streets of Aronburg. There are three of these that have been able to look at the larger picture, spend more time building an infrastructure, and taken measures to set up semi-legitimate businesses they can use to conceal their criminal activity.
One of these is the local Thieves' Guild, which has bought most of the docks and warehouses in town, and profits by allowing illicit smuggling to occur alongside regular trade. They tend to skim a stiff percentage on most items they handle, calling it a tariff on trade if pressed to defend. Their intent is to be subtle and low-impact, so their presence and activity will be tolerated. They are more directly responsible for policing the waterfront than the actual town guard, though the guard is ignorant of the extent of their influence.
Another large group operates out of the marsh and swamp across the river north of town. This is a well-organized group, but they are small in number. They hire mercenary smugglers and thieves when they have need, rather than have a regular number of associates. They are known as a ruthless band of thieves, and operate largely unknown to the townspeople. The guard is aware of their existence, but have been unable to track the leaders down. Because they are based in the swamp, and run by a tight-knit, small group of bandits, they have proven difficult to locate.
The final group is the largest and best organized of the three, at least in terms of criminal activity. They operate entirely within the shadows behind a successful, legitimate concern. They have their own boats, docks and warehouses on the western shore - away from prying eyes, away from the guard, and away from the townspeople and their concerns.