Online shoppers like being able to pick up a web order at a local store, but in-store pickup presents operational and logistical challenges to retail chains.

In the new report, “Nailing In-Store Pickup,” Forrester Research Inc. analyst Brendan Witcher says retailers are challenged to meet customer expectations about in-store pickup and those expectations are only going to rise. More than half, 53%, of the more than 3,000 online U.S. adults surveyed say they expect notification in two hours or less that orders are ready for pickup. Those expectations are likely set by some retailers’ aggressive promises. For example, Best Buy Canada guarantees orders placed online will be ready for in-store pickup within 20 minutes.

70% say they use buy online, pickup in-store services, mostly to avoid shipping costs. Other popular reasons are convenience, to ensure the product is available and reserved for the shopper, to get the product the same day and to avoid taking the time to find a product in the store.

But while shoppers like in-store pickup, the offering isn’t simple for retailers to master. In-store pickup requires merchants to have up-to-the-moment inventory data, sufficient store staff and a designated area where shoppers can pick up purchases. Witcher says retailers should not offer all products stocked in their stores for pickup because some are too taxing on the store to manage in a timely fashion (think bulky appliances) or they are in high demand and actual inventory cannot be reliably guaranteed.

Communicating which products are and are not available for in-store pickup is important. Witcher says this information should be called out on product description or product listing pages.

Nearly a third, 32%, of the retail chains ranked in the Internet Retailer 2014 Top 500 Guide offer consumers in-store pickup of goods ordered online.