The recent Twitter popularity of the #MeToo movement (originally started by activist Tarana Burke) has shone a public spotlight on ongoing conversations about rape and sexual assault.

There is no single, magical solution to the problem of sexual assault, but an important piece of the puzzle is changing the way we understand sex and consent. Prevailing social rules excuse—or actively encourage—powerful people who exploit the less powerful, and they make even consensual sex a needlessly unpleasant experience. Fortunately, more people and institutions are coming to embrace a better standard: affirmative consent.

What is affirmative consent?  California’s SB 927, which requires all state universities to adopt an affirmative consent standard, states that

“Affirmative consent” means affirmative, conscious, and voluntary agreement to engage in sexual activity.

The bill contrasts affirmative consent with “lack of protest or resistance;” someone who is not communicating about whether they want a sexual activity is not consenting to that activity. The bill also specifies that if someone is incapable of conscious consent—either because they are unconscious, or because they are too incapacitated to “understand the fact, nature, or extent of the sexual activity,” they cannot conesent to sex. “Voluntary” implicitly rules out cases where consent is coerced by threats.

Under an affirmative consent standard, people do not consent to “sex” in general, but to particular activities; agreeing to touching doesn’t mean agreeing to penetration, and agreeing to penetration doesn’t mean agreeing to penetration without a condom. Consent can be withdrawn at any time: someone who goes to their date’s apartment to have sex, but changes their mind as soon as they walk in the door, does not count as consenting to sexual activity.

Notice that “affirmative consent” does not equal “verbal consent”. Verbal consent obtained by coercion or deceit fails the “conscious and voluntary” requirement. And consent can be affirmative without being verbal; someone who responds to their partner’s “may I kiss you?” with an enthusiastic kiss is giving a clear, nonverbal signal of agreement. Furthermore, it’s possible to frame a verbal request for consent without speaking in dry, legalistic terms. It’s just as easy to say “let’s make out” or “kiss me, you fool” as it is to say “I hereby request your consent for a kiss.” Maybe even easier.

Some common objections to affirmative consent misunderstand the concept. Won’t affirmative consent ruin what’s sexy about sex?, critics ask. What about people who want their partner to take charge, or who find it unsexy to be asked before every sexual activity—aren’t their preferences legitimate?

Fortunately, affirmative consent is compatible with a wide variety of preferences practices. Someone who likes to be spontaneously grabbed can communicate this at the outset of their relationship, then settle in for a long, happy future of surprise groping. Two people starting from positions of equal power can negotiate a dynamic where one of them takes charge in specific settings. People who enjoy the thrilling touch of strangers can even set up clearly labeled clubs where such touch is allowed and encouraged. Affirmative consent demands only that the participants enter those dynamics freely and knowingly, and that they be allowed to leave if they change their minds.

Another misguided objection claims that a standard of affirmative consent infantilizes women and treats them as incapable of meaningful sexual agency. Defenders of this objection make the same mistake they attribute to advocates of affirmative consent: they project simplistic gendered assumptions onto a rich and complicated reality. Not all victims of sexual assault are women, and not all perpetrators are men. Everyone, not just heterosexual men, should be held to a standard of affirmative consent.

A more compelling objection concerns interaction between affirmative consent and institutional punishment. Won’t adopting a legal standard of affirmative consent result in more people being unjustly punished? It is true that the criminal justice system in the US is marred by racism and brutality, and expanding any legal punishment is likely to lead to additional injustice. This is as true of punishments for theft and murder as it is of punishments for sexual assault.

The criminal justice system needs a comprehensive overhaul, but the answer is not to selectively relax our standards for sexual assault, while holding the standards for other crimes fixed. A standard of affirmative consent (which determines what counts as a crime) is compatible with a greater respect for due process (which sets high standards for proving that someone has committed the crime they are accused of). Even if legal scholars determine that affirmative consent is not the right standard for criminal law, we should uphold it as a moral standard, and perhaps as a standard for extra-legal institutions.

There are many ways to ask for consent, and many ways to give it. Your communication doesn’t have to satisfy arbitrary formal rules picked out by a cabal of social justice experts. But if you want to have sex, you do have to communicate.