The Corridors of Hope Project (COH) aimed to reduce sexual transmission of HIV among female sex workers and their clients residing in or passing through border towns or other key communities. To monitor and assess progress of prevention interventions,  repeated rounds of cross-sectional behavioral and STI prevalence surveys (Behavioural and Biologic Surveillance Surveys, or BSS) were conducted.

The Round 1 BSS was conducted in 2000 among truck drivers only. The Round 2 BSS, conducted in 2003, included truck drivers, uniformed personnel, light truck and mini bus drivers. A third round BSS was carried out in 2006 among long distance truck drivers passing through two of the border project sites (Chirundu and Livingstone/Kazungula) and one inland site (Kapiri Mposhi). Long distance truck drivers at Chirundu and Livingstone participated in all three BSS.

The general objective of this third round of BSS was to monitor the outcomes of existing prevention interventions through a cross-sectional assessment of risk