Senior PSNI officers have voiced qualified confidence that tonight's Orange march in north Belfast will pass off peacefully.
Up to 1,000 Orangemen, including 22 bands, will parade along a 7.5km route and past republican Ardoyne, where a protest is expected.
The Tour of the North march, as it is known, is the first major loyalist parade in the city this year and it sets the tone for the rest of the marching season.
This is the first time determinations by the Parades Commission, which rules on contentious marches, have laid down conditions which also apply to parade supporters and protesters.
The commission has set down restrictions on the march as it passes a 450m stretch near the Ardoyne shops. This was where trouble flared last July 12th as Orangemen walked home to Ballysillan from the city centre.
Police say Parades Commission rules will be enforced and Orangemen will not be allowed to play music as they pass Ardoyne. The marchers' supporters, family members and friends will also be allowed to walk through the area subject to conditions. Three local Orange bands will be subject to specific terms of the commission's ruling.
Policing of the event follows contacts between PSNI officers and residents, representatives of the Loyal Orders and others.
Despite their confidence, PSNI officers say they will be prepared for any trouble. Although Ardoyne is an obvious potential flashpoint, there are other possible trouble spots along the route.
The PSNI insists that officers available will be proportionate to the scale of the parade being policed and any accompanying protest. This is understood to mean that about 600 officers will be available.
Police can call on British army support as well as on a range of other resources including water cannon.
There will be screening, lines of PSNI Land Rovers and temporary railings at key sections of the route but these will not be in place until just before the parade begins and will be dismantled shortly after the marchers pass.
Other planned demonstrations have given rise to political tension. In east Belfast, controversy surrounds another major planned march as the Parades Commission insists on precise completion of the form used to request permission to stage a parade.
Information demanded on the application form includes contact details of an individual organiser. Some in the loyal orders feel this is unfair, while the commission insists the application form must be filled out completely.