In the asphalt-versus-concrete for pavements controversy highway officials often say there is a place for both. But where is that place? In the past, one sure place for asphalt on concrete paving projects has been the shoulders. This has changed in recent years since the concrete paving industry has forged ahead with the idea that concrete shoulders are the coming thing. They contend that concrete shoulders prevent differential settlement between shoulder and pavement, eliminate the need for constant resealing of the pavement-shoulder joint, and reduce stresses at the pavement edge, thus prolonging pavement life. Concrete paving interests are also promoting hard the use of their product for resurfacing, a huge market that has long been almost exclusively the realm of the bituminous sector. It there is a place for both paving materials it depends on local conditions: climate, soils, aggregate availability, prices for asphalt and portland cement, and availability of qualified contractors. In Ohio, there is a problem with certain coarse aggregates when they become saturated, causing the concrete to disintegrate by D-cracking. However, there susceptible aggregates perform satisfactorily on streets in Columbus and elsewhere in Ohio in concrete bases with asphalt surfaces. Both industries realize that the big market in highway construction is now the upgrading of existing facilities, particularly the long-neglected primary system. Renewing existing pavements with overlays is a major part of this program. One example is the recent idea of using open graded asphaltic concrete (popcorn mix) surfaces. These mixes utilize single-size aggregates which allow surface water to percolate down to the relatively impermeable original surface. From there it flows laterally to the roadside. The pavement surface remains free from excess water, reducing the dangers of skidding accidents.