The new brief, understood to be worth a mid-six-figure sum, will not affect Nespresso's relationship with Weber Shandwick, which includes handling global social media duties.
Nespresso is fronted by film star George Clooney and has driven growth in the coffee capsule and coffee-maker market.
However, its success has attracted competitors with the Nestle-owned $4.4bn (£2.7bn) brand, although efforts to obtain a definite sales ban on producers of copycat coffee capsules have so far been unsuccessful.
The brief revolves around a specific, though undisclosed, initiative aimed at strengthening the business.
One well-placed source said the work was focused on "helping with an overarching strategy" across a wide range of markets.
"It has lots of products and global coffees," they added. "It's about what concept it wants to link it all together."
This summer Nespresso assembled its first board of experts to advise it on a long-term sustainability strategy.
Earlier this month YouTube made it the first European partner for a scheme aimed at providing brands with the tools and training to improve their content on the site.