【正文】 Rfacilities at the terminus stations of the municipal UBahn or SBahnstations where train capacities provide a good chance for the passenger to get a seat. Pamp。s own premises and, second, to pay a certain amount of money per space to the munity. These payoffs are used to provide spaces within an acceptable distance or to finance park andride spaces within the munity or even in neighbouring munities. Originally, the second way to discharge the obligation was limited to cases where the premises were not suited for providing parking spaces because of size, lack of access or reasons of urban protection and renewal. In recent years, the application of discharges was extended and bined with a limitation or even prohibition of building new parking spaces in heavy trafficked areas with reasonable public transport alternatives. The munities were authorised by the Building Acts of the States to regulate the amount of private parking spaces by local ordinances. Basically, the parkingspace obligation is maintained, but only a certain part (or no part) of it can be realised through parkingspace provisions, whereas the rest must be payed off. At the moment, parking space limiting ordinances are known from seven cities, several more are preparing such ordinances. Usually the limitations concern offices, whereas flats are handled differently. The payoff amount per space is limited to 60 to 80% of the real costs to build a space in the area concerned. The local ordinances fix the maximum amount which is mostly staggered according to city zones. The maximum payoff amount varies between DM 10,000 and DM 30,000 per space. Actually (Stadt Frankfurt am Main, 1990 and discussions about the amendment of the Berlin Building Act), the extended use of payoffs for public transport is being discussed (and now, since September 1990, legally introduced in Berlin). Until now, use is limited to parking facilities including parkandride except in Berlin. 6. Parkandride concept of the City of Frankfurt Parkandride is one of the most popular issues among traffic planners in Germany. Compared to this, the existing Pamp。 vehicles had to be parked on private premises. Since 1939 (Reichsgaragenordnung),in Germany building owners are legally obliged to provide parking space on their premises according to the type and amount of intended uses. In the meantime, parking within the public street has bee mon law. But nevertheless the Building Acts of the German States still formulate the parking space obligation. The parkingspace obligation es into power when a building is newly erected, when it is rebuilt or extended or even when the uses of the building are changed. If, for instance, a flat is converted into an office, the parking space obligation is extended from 1 to spaces per flat to 1 space per about 30 m 2 usable area。 it works with market tools as well as with planning and administrative tools. Parking permits for resi dents, limitedperiod parking and parking charges are the most important instruments to control onstreet parking. The charges at parking meters and parkomats (pay and display) are legally limited to DM 2 per hour, although most cities take DM 1. In general, parking prices at onstreet spaces which are usually the most fortable and nearest, should be clearly higher than those offstreet in parking garages. Although the instruments of areawide parking management were pleted with the introduction of residential parking permits 10 years ago, only a few cities have installed such concepts, among them Aachen, Heidelberg, Kassel and Saarbriicken. Despite frequent discussions about parking concepts among planners and politicians, only a few studies of the effects are available. A beforeandafter study within the same year in Munich (ADAC, 1982) shows the effects of residential parking permits on the modal choice of employees. The share of car solodrivers dropped from 44 to 32% and the traffic peaks and search traffic during the day were reduced. Spillover parking in neighbouring streets was not observed。 next is to distribute scarce spaces according to priorities derived from urban development policies。s parking space. That means a fivefold car traffic generation if a parking space is transformed from longduration use of residents or employees to short duration of customers, as is often discussed in parking concepts. AdditionaUy, the imbalance of the demand for public transport services during the day will increase with the effect of growing operating costs. More car traffic also out of traffic peaks is not bearable in the large cities because of air pollution. Therefore, the formula must be extended: more shortduration spaces for customers instead of longduration spaces to the extent that car traffic will not increase in total. That could be achieved, for instance, if five longduration spaces for employees are transformed into one short duration space for customers and one long duration for residents and the rest changed into pavement, cycle lane, bus lane or space for a tree. Consequently, the Clean Air Program for the City of Stuttgart (Steierwald et al. 1988) prefers the reduction of shortduration parking spaces to those of longduration. The parking concept of the City of Frankfurt (1988) is based on a drastic reduction of employees39。 cars parked onstreet in a Frankfurt inner city district are not moved during a weekday. In Munich inner city districts, this share of unmoved cars rises to 30%. Residential parking spaces used in this way generate no car traffic during the day at all. On the contrary, a parking space with a onehour parking limit from . to . which is enforced, may be occupied 10 times, thus generating 10 car arrivals and 10 departures. Rough balances are often based on the assumption that a shortdura