One of the biggest obstacles that contractors face when using construction software is interoperability. According to a recent McGraw-Hill report, Interoperability in the Construction Industry, roughly 3.1% of the cost of a construction project can be attributed to the lack of software interoperability. That amounts to $36 billion for the US construction industry. Sister site SearchSOA.com defines interoperability as "the ability of a system or a product to work with other systems or products without special effort on the part of the customer." If you have ever manually re-entered data into two or more applications or had several applications open to create a report or fulfill an RFI, then you have exerted "special effort." At the most basic level of interoperability, an application will let you import a data file from a format defined by another application, most notably Microsoft Excel, Adobe Acrobat, QuickBooks or Crystal Reports. Other examples, which were presented during the Software Showcase sessions at last week's AACE International Annual Meeting in Toronto, include project management software tools that let users import data from scheduling software such as Primavera P6, Primavera SureTrak or Microsoft Project. File importation is a key consideration for contractors who intend to migrate to construction-specific software and want to make sure that decades of key data will not be lost in translation. It is also worth asking if those files are imported as Read-Only files or can be edited once they have been imported. Many vendors take interoperability one step further and indicate that their product will integrate with another product. To build on the previous example, integration can be seen as the ability to use one application to view data being stored in another. For example, many construction software applications, including those from Primavera, ARES and CMiC, will integrate with back-end systems, such as Oracle, SAP and JD Edwards, to give users access to financial information. (I am sure that many other vendors link to back-end accounting systems. If you know of any that I missed, please leave a comment below.) One interesting example from the AACEI software showcase was Hard Dollar. In addition to letting users import cost data from Excel, Hard Dollar integrates with Primavera software, to the point that changes made in one application are automatically reflected in the other. With the most recent version of Hard Dollar, users can also map Hard Dollar tags to Primavera fields and transfer Hard Dollar account codes to Primavera. (Our Hard Dollar vendor overview provides some additional information about integration with Primavera.) I decided to bring up interoperability and integration after hearing a few tales of interop nightmares from AACE International attendees. One project manager said he had to ask the finance department, in person, to pull cost data from the SAP accounting system -- he knew the data was there, but he couldn't get it himself. Another project manager learned the hard way that Primavera software would only import Microsoft Project documents if they were from the 1998 version. A third attendee noted that a number of large construction firms overcame interoperability problems by simply building their own software systems. (Our own reviews of Faithful+Gould's EPOCH and Bantrel's EPCWorks provide a couple examples of this.) Multibillion-dollar construction companies can afford to build software. You can't. That's why it's especially important for you to ask about interoperability and integration when you are considering construction software. The last thing you want to do is settle for a solution that does not work with the software that you already have and thus further disrupts the business processes you have worked to develop. If nothing else, you can boil interoperability down to a number -- 3.1%. You can either spend that much of a project's total cost on tedious office tasks, or you can aim to reduce costs and win more bids. In a market as volatile as today's, 3.1% can make all the difference.