Wrong-way crashes are a major cause for safety concerns along freeways and limited-access facilities. Although wrong-way crashes account for a relatively small portion of total crashes, the impact between two cars crashing into each other at high speeds in opposite directions often results in severe injuries or fatalities compared to any other type of crash. To seek solutions for mitigating wrong-way driving (WWD), multiple field tests involving a number of countermeasures using Intelligent Transportation Systems (ITS) technologies have been conducted in Florida. This study was aimed to evaluate these WWD countermeasures in Florida and develop recommendations regarding the most effective and informing WWD countermeasures through (1) analysis of existing data and studies, (2) field WWD testing using focus groups, (3) a public opinion survey, and (4) capturing human factors elements using simulation via a driving simulator. The results proved that red Rectangular Rapid Flashing Beacons (RRFBs) are the top countermeasure for mitigating WWD at freeway off-ramps, with wigwag flashing beacons as the second best, and detection-triggered blank-out signs and detection-triggered LED lights around “WRONG WAY” signs (tie) as third best. Red flush-mount Internally Illuminated Raised Pavement Markers (IIRPMs) were found to be statistically significantly effective for possible consideration as a supplemental countermeasure for mitigating WWD at freeway off-ramps. The countermeasure of delineators along off-ramps was found to be the least effective and was not considered for recommendation for deterring WWD at freeway off-ramps. This study further confirms that the newly-developed signing and pavement marking standards in Florida are a positive countermeasure on arterials to mitigate wrong-way entries onto freeway off-ramps.