Dive Brief:

• Wal-Mart's chief merchandising officer has announced his departure from the retailer in a memo Monday. 
• Duncan Mac Naughton has been at the retailer since 2009, where he started as chief merchandising officer of Wal-Mart Canada. 
• The memo declined to name Mac Naughton's replacement. 

Dive Insight:

With Black Friday just around the corner, this high-level change up came as a surprise to many.

Wal-Mart has been struggling for the past two years to boost sales and increase shopper traffic in stores, although it did record its first uptick in comparable sales in seven quarters this last quarter.