Assessing the Cost-Effectiveness All three major undertakings, the Evros fence, Operation Shield and Operation Zeus served a wider spectrum of objectives: restore public order, protect public health, combat criminality, enhance tourism, and improve the working conditions of police officers in 'problematic' areas. Within the context of irregular migration management however, the main objectives were two: 1. to stop irregular arrivals by targeting specific entry points 2. to arrest and detect irregular migrants who nonetheless managed to cross the border, with a view to returning them to their home countries. The main tools to achieve this were: (a) the construction of a technical barrier and physical presence on the one hand; (b) deployment of specialised officers and sweeping round-up operations on the other. A. Preventing irregular arrivals through technical barriers and physical presence A1. Direct costs and direct outputs In terms of direct outputs, for the period 2008-2012 arrivals and apprehensions were relatively high at the land border. However, from 2012 to 2013, and in the aftermath of the Evros fence and Operation Shield there was a dramatic 96% reduction in registered irregular arrivals at the Greek-Turkish land border. At the same time however, there was a relative 231% increase in apprehensions at the sea border, previously reduced to couple hundred arrivals per annum. Parliamentary Discussion of 22 October 2012, p.2934, during which, the then Minister of Citizen Protection mentioned that Operation Xenios Zeus was co-financed by the European Refugee Fund available at http://www.hellenicparliament.gr/UserFiles/a08fc2dd-61a9-4a83-b09a-09f4c564609d/es20121022.pdf Page 30