Research Article Transportation Research Record 1–10 Ó National Academy of Sciences: Transportation Research Board 2019 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0361198119854086 journals.sagepub.com/home/trr Impact of Utilizing Construction Engineering and Inspection Consultants on Highway Construction Project Cost and Schedule Performance Ying Li 1 , Sara Al-Haddad 2 , Timothy R. B. Taylor 1 , Paul M. Goodrum 2 , and Roy E. Sturgill 1 Abstract State transportation agencies (STAs) are tasked with constructing and maintaining complex transportation networks while facing changes in agency construction staff with respect to age, experience level, turnover, retirement, and increasing levels of consulting services that are used to manage STA construction operations. To keep up with the increasing demands of proj- ects, STAs are utilizing Construction and Engineering Inspection (CEI) consultants to fill the demand for construction-related human resources. However, the impact of using CEIs on project cost and schedule performance has not been quantified. The current work addresses this knowledge gap by analyzing a database of 305 completed highway construction projects across 16 STAs. The analysis found that projects that utilized CEI consultants had higher levels of full-time equivalent construction staffing than projects that utilized only agency staff. The use of CEI consultants had no impact on project cost compared with projects that relied solely on agency staff. Projects that used CEI consultants had an average cost overrun of 20.2% compared with agency-staffed projects, which experienced average schedule overruns of 27.7% (i.e., the project, on average, finished early). The schedule difference was statistically significant. State transportation agencies (STAs) are increasingly constructing more complex projects under more competi- tive schedules. This evolution is occurring at a time when STAs are experiencing significant staff turnover. Experienced personnel are leaving STAs through retire- ment and are being replaced by less experienced person- nel who are experiencing more rapid increases in their responsibilities earlier in their careers than their prede- cessors. In some STAs, retiring personnel are not being replaced at all. These changes are affecting all divisions of STA personnel, particularly those tasked with the con- struction of highway infrastructure (1, 2). NCHRP Synthesis 450 found that among 40 STAs, between 2000 and 2010, state-managed lane miles increased by an aver- age of 4.1%, while the number of full-time equivalent staff decreased by 9.7%. When full-time equivalents (FTEs) were normalized across the managed road sys- tem, the responding STAs’ FTEs per million dollars of disbursement on capital outlays decreased by an average of 37.3% (3). In response to increasing workloads and diminishing staff, STAs have outsourced various func- tional activities traditionally performed by in-house per- sonnel. The diversity and volume of services that Construction and Engineering Inspection (CEI) consul- tants provide, along with the nature of their services, make their role critical (4, 5). STAs would benefit from guidance on how best to utilize construction staffing resources, including CEI consultants. While STAs are using CEI consultants to staff agency projects, the impact of using consultants on project cost and schedule performance has not been quantified on a large scale. The content of this paper focuses mainly on the effect of using CEI consultants on highway construction project performance and staffing level requirements. More specifically, this paper contri- butes new knowledge on:  When and for what functions CEI consultants are used for highway construction projects. 1 University of Kentucky, Lexington, KY 2 University of Colorado, Boulder, CO Corresponding Author: Address correspondence to Ying Li: ying.li@uky.edu