This approach involves a range of friendly and not-so-friendly meetings before and during a protest action aimed at controlling, changing, or affecting the nature of the event and outcome of the action. The policing of the 1998 maritime dispute is a very good example of this type of policing (Baker 1999).
Police may politely request that activists stick to the footpath, move from an area or move a stall, for instance. Sometimes these requests or directives might be made with the implied threat of arrest if the request/directive is not obeyed. The threat to arrest, in the event that the request/directive is not obeyed, might be followed through or might simply be a bluff. It is often difficult to know in advance and ultimately police tactics will be influenced by a variety of factors (also see Why police choose certain approaches). Directives are often aimed at police maintaining control over a protest action.
Police can approach individual activists and make requests or give directives. This often proves an effective way to control a protest. Understanding police techniques is valuable and learning to assert your rights when requested to do something by police is an important activist skill.
It can be valuable and useful to engage in liaison with or negotiate with police if you are aware of the potential pitfalls. However police liaison can be very difficult and intimidating.