FROM THE rolling hills of horse country to the subdivisions of the young professionals and the small farms still holding fast along the back roads, Loudoun County is hearing eerie echoes of campaign debates that neighboring Fairfax heard 15 or 20 years ago. The land of Loudoun has caught the roving eye of growth -- and the election of county supervisors is all about how to react to the complex dynamics. The districts within the county and the political options they offer vary markedly -- as do the vision and experience of those seeking to manage the government. The common thread is a classic pursuit of balance -- a reasonably reliable tax base, elbow room, local services and convenient passage from here to there, all without the mistakes of Fairfax or any other part of the region that has undergone change.

One candidate who perhaps best reflects the informed and thoughtful approach to a balanced future in Loudoun is Betty Tatum, incumbent Democrat and current chairman of the board who is running unopposed in the Guilford District. Her low-key, middle-of-the-road style has won her respect not only around the county but also on the regional policy-making board of the Metropolitan Washington Council of Governments.

In the Dulles District -- which is fast becoming the economic backbone of the county -- the growth issue is as hot as anywhere and has sparked a three-way race. Republican challenger Benjamin H. Hicks Jr. charges that the current board majority is inept and that this district has been "sacrificed" to developers in an effort to spare the western end of the county. Independent Clement J. Berezowski, who is outspending each of his two opponents with a largely self-generated campaign fund, has emphasized transportation improvements but has failed to offer outstanding thoughts on much else. Incumbent Democrat Ann B. Kavanagh couples her calls for "orderly growth" with a working knowledge of county, state and private financing options for roads and other public services -- which makes her well worthy of reelection.

Another three-way contest, in the still mostly rural Blue Ridge District, pits a 20-year board member, Republican-turned-independent James F. Brownell, against Republican challenger Larry Johnson and an independent endorsed by local Democrats, Ben Fordney. Mr. Brownell has been a vigorous critic of much of the county's growth but cites limits to the government's ability to stop it; he stresses the necessity of a sophisticated planning arm and of exacting road, sewer and other service commitments from developers. Mr. Johnson has seemed more concerned with decrying the level of county spending and sex education in the schools. Mr. Fordney, who lost a close race to Mr. Brownell four years ago, argues that Mr. Brownell's style is too passive and pledges coordination with the western Loudoun towns and the county board to protect them from overwhelming growth. The choice should be between Mr. Brownell and Mr. Fordney; whether Mr. Fordney can make a strong enough case for unseating Mr. Brownell remains to be seen.

In the Broad Run District, incumbent Steve Stockman, who holds office as an independent but is running as a Republican, believes in attracting business to bolster the county's economy. Independent challenger Gregory R. Marquis argues that the board is not paying attention to the management of water, sewage and problems created by rapid growth. Mr. Stockman's extensive knowledge of development options has proven valuable to the board -- and makes his reelection a plus.

In the Catoctin District, Republican incumbent Frank I. Lambert, supporter of development, is challenged by Democrat Betsey Brown, who is a strong proponent of open-space preservation. Given the expertise of other board members in working with developers, the next mix of supervisors might well benefit by the challenging presence of Betsey Brown.

In the Leesburg District, incumbent Democrat Charles A. Bos has experience in zoning and bond matters that makes him a stronger candidate than Republican challenger Georgia White Bange. In the Mercer District, incumbent Democrat Thomas S. Dodson has a more balanced view of growth issues than Republican challenger G. Lawrence Moison. And in the Sterling District, independent Alice Bird has waged a commendable campaign against her former husband, Republican incumbent Andrew R. Bird III, but Mr. Bird's proposals for balancing and accommodating future growth argue strongly for his reelection.

County voters also have a $15-million parkland bond referendum on the ballot. The proposal is for a sound investment, deserving approval.