Recent years have seen a veritable surge in the popularity of social media micro-influencers among the younger generations like Millennials and Generation-Z. These amateur micro-influencers have achieved a modicum of fame through their charismatic appeal and niche expertise, by focusing on a very narrow domain of interest within a large set of product and service categories. The growing popularity of micro-influencers has not escaped the attention of online fashion and streetwear marketers, like Asos, Boohoo, and Fashion Nova, who have coopted them to present their offerings on social platforms, like Instagram, using rich, visually appealing content, often modeled by the influencers themselves. This novel marketing and branding approach is highly cost-effective and obviates the need for traditional and expensive push marketing methods like television advertising and celebrity endorsements. Moreover, some of the micro-influencers themselves are now leveraging their social media popularity to launch their own “private fashion brands” on Instagram. These online developments have gained even greater momentum during the time of the pandemic. All such emerging tactics and trends stand to disrupt many mass-market apparel companies like Gap, Zara and H&M. The paper concludes with a set of managerial implications for practitioners of these established firms.