Speaking at the Cosmopolitan: A Celebration of Female Talent event at a packed out Kensington Palace, she explained: "Women are not being paid enough, we are not being promoted enough and mostly we are treated appallingly. it’s not good enough.
"There are not enough women in middle management positions and there are not enough women in senior positions in advertising. We should not be patting ourselves on the back."
Addressing the predominately female crowd, Robertson also noted that without the support of male colleagues "nothing is going to change".
Tracy De Groose, chief executive officer, Dentsu Aegis Network UK, used the spotlight to highlight that there aren’t enough female role models in the industry but added: "You can do it and have a life and a family."
Her sentiments were echoed by Annette King, CEO of Ogilvy & Mather Group UK, who advised the audience to "find a place to work where you can do it all – have the family, have the balance and fit it all in."
While Syl Saller, chief marketing officer at Diageo pointed to the business benefits of supporting female talent. She explained: "We now have five women on our board and six women out our exec team and it makes a huge difference to our business.
"I hope all women have the support they need to succeed."
The event, which was part of Adweek Europe, celebrated female advertising industry icons and saw King, Saller and De Groose recognised by Hearts as part of its Empowering Women initiative.