Fellow fashion designers including Donatella Versace and Anna Wintour paid their tributes to Lagerfeld, honouring the "creative genius" and "incredible talent" of the designer best known as artistic director of Chanel.
To mark his passing, Dezeen looked back on 12 of his most impressive runway shows, which included transforming Paris' Grand Palais into an enchanted forest, and constructing a recreation of the Eiffel Tower.
The design industry also had to say goodbye to Italian architect, designer and theorist Mendini.
As well as serving as editor of Italian design magazines Casabella, Modo and Domus, Mendini designed numerous influential designs including Proust armchair, Groninger Museum and the Anna G corkscrew.
The fashion world slipped up again this week, as Burberry released an apology for the "insensitive" design of its hoodie with a cord that looked like a noose, which was worn by a model during London Fashion Week.
Also at London Fashion Week there were protests with Vivienne Westwood creating a collection with slogans berating politicians, and action group Extinction Rebellion demonstrating to highlight the environmental impact of the fashion.
At Milan Fashion Week, Moncler unveiled a collection of padded full-length evening dresses by Valentino creative director Pierpaolo Piccioli, as a reinterpretation of the outdoor clothing company's down jackets.
Over in the field of tech, Samsung hit the headlines this week when it released a foldable device, the Galaxy Fold, which unfolds "like a book" from a smartphone into a tablet.
Layer developed a smart textile for use in Airbus' economy class seating, which is digitally knitted with sensors that detect both the passenger's body and the conditions of their chair to allow the user to control the conditions using their phone.
In the US, reservations have opened for guests wishing to stay inside the former TWA Terminal of New York's John F Kennedy airport, which has undergone a major overhaul after being shut for 16 years.
Dutch architecture firm OMA designed an escalator for the Saks Fifth Avenue department store in Manhattan, which has glass panels that change colour when viewed from different angles.
Popular projects this week include Gus Wüstemann's affordable apartment block made almost entirely from concrete, Melike Altınışık Architects' plans for a Robot Science Museum in Seoul that will be built using robots and drones, and the return of California's Desert X installations.