When you get excited in one of Studio Roosegaarde's dresses, you just can’t hide it.

The social design lab helmed by artist Daan Roosegaarde (and based in Waddinxveen, Netherlands and Shanghai) has created a line of high-tech dresses that become transparent based on personal interactions between partners -- or whenever the wearer gets aroused.

The dresses, aptly named “Intimacy,” are designed by Anouk Wipprecht and constructed from leather and smart e-foils that monitor the wearer’s heart rate. The higher BPM, the more see-through the dress becomes. Prior to stimulation, the dress is one of two colors: “Intimacy White” or “Intimacy Black.”

“It creates a situation of total control that the wearer or the one who observes it has an influence over what fashion looks like,” Roosegaarde told The Daily Beast.

Roosegaarde and his team have long been fascinated by the notion of technology and electricity combining to create more interactive and open environments. Other projects by Studio Roosegaarde include a sustainable dance floor that generates electricity through dancing and a “smart highway” that uses light and energy to adapt to traffic. When Roosegaarde decided to apply his technological ideas to fashion, Intimacy was born.

Each dress has a small microchip embedded inside that contains software programmed to monitor different behaviors—in this case, a heartbeat. The garment functions much like a computer: The input is the heartbeat, the processor is the microchip and the output is the foil material, which can change from white to transparent or black to transparent.

Still, Roosegaarde stresses that the Intimacy line is not so much about the technology as the human interaction it spawns. He was intrigued by the various signals exchanged between partners, as well as the idea of hiding and showing things, such as when one unbuttons or buttons up their shirt or pants.

“With some people you want to show more and some people you want to show less,” Roosegaarde said. “We thought it would make complete sense that the dress would be proactive in that: either you have control or you lose control.”

The Intimacy range began in 2011 as an art project designed by Maartje Dijkstra and led to the latest incarnation, Intimacy 2.0. According to Roosegaarde, a high-end line is also in the works, as well as Intimacy 3.0, a suit for men that becomes transparent when you lie.

“That’s for the banking world,” Roosegaarde said with a chuckle.

For now, the Intimacy collection is only available to private collectors, but Roosegaarde said they plan for a wider dissemination soon.