Harford County, population 218,590 (2000), is located 15 miles northeast of Baltimore, just south of the Pennsylvania border. The County actively promotes several optional agricultural preservation programs. In a March 2005 update, Daniel E. Rooney, AICP reported that the Harford County Agricultural Preservation Program had preserved over 37,000 acres as of 2004. The County also has a TDR program available in its Agricultural District.

Beyond Takings and Givings describes the Harford County TDR program as it existed prior to 2003. In April 2003, the County Council adopted amendments to the TDR program designed to provide conditions and restrictions under which development rights may be transferred.

Prior to this amendment, sending and receiving sites had to be within 500 feet. The 2003 amendments allow transfers to receiving sites that are with one-half mile of the sending site.

The baseline density in the Agricultural District is one unit per ten acres. Prior to the 2003 amendments, the maximum density allowed on receiving sites was one unit per acre, theoretically offered a 900 percent bonus. The 2003 amendments now limit the bonus density on receiving sites to a maximum of 50 percent above baseline density.

The 2003 code change also specifies that development rights can only be transferred once. In addition, the amendments clarify that once TDRs have been transferred from a sending site, that site cannot receive other TDRs.