The books on this subject disagree with each other, and that disagreement is the reason to read several of them. An evolutionary psychologist and a couples therapist looking at the same married pair will describe two different situations, and both descriptions will hold up. A reader who takes one author as the final word ends up with a confident theory that fails on contact with an actual person.
The seven books about modern relationships here have all survived a decade or more of replication attempts and public argument. Several have been revised more than once because the research underneath them moved.
The Evolution of Desire by David Buss
Buss published the first edition in 1994, with revised editions in 2003 and 2016. The book is built on his 1989 cross-cultural study of 10,047 people across 37 cultures, still one of the largest datasets on stated mate preference ever gathered.
The findings are blunt and have held up under replication. Women rated good financial prospects higher than men did in 36 of the 37 cultures. Men rated physical attractiveness higher in every sample. Buss treats these as evolved strategies rather than social accidents, which is where most of the criticism of him begins. Critics argue that stated preferences track the economic position of women in each society, and Buss answers that the pattern holds even in the most egalitarian samples he collected.
Read it first, because almost every other book about Modern Relationships on this list builds on Buss or argues against him.
Attached by Amir Levine and Rachel Heller
Published in 2010, this is the book that moved attachment theory out of clinical journals and into ordinary conversation. It has sold more than 2 million copies, and the anxious, avoidant, and secure categories it popularized now show up in conversations between people who have never read a psychology paper.
The practical value is in the pairings. Levine and Heller argue that an anxious person and an avoidant person will produce a specific, predictable cycle of pursuit and withdrawal, and that recognizing the cycle early saves years. Its neatness is also its weakness. Real people move between categories depending on who they are with, and the book is more categorical than the research it summarizes.
The All-or-Nothing Marriage by Eli Finkel
The argument here is demographic and historical. Marriage once served physical safety and household economics, then love and companionship. Now it is expected to serve self-actualization, a heavier load placed on one relationship than any previous generation attempted. Eli Finkel, a psychologist at Northwestern, laid this out in 2017 and called the climb Mount Maslow, and his point is that the air gets thinner near the top.
The consequence he documents is a widening gap. The best marriages now are better than the best marriages of the 1950s by most measured standards, and the average marriage is worse, because the higher expectations only pay off when both people invest heavily in each other. It is the most useful book here for anyone trying to work out what they are actually asking a partner to provide.
Polysecure by Jessica Fern
Fern, a psychotherapist, published Polysecure in 2020 and extended attachment theory into consensual non-monogamy, which nobody had done in a serious way before. Her nested model treats attachment as something operating at the level of self, relationship, and community at the same time.
The book is worth reading even for people with no interest in multiple partners and Modern Relationships, because it forces a question most monogamous readers never ask about what they actually want from exclusivity. Someone who decides they are ethically monogamous after reading Fern has made a choice, and the person who never examined the question has only inherited a default. Roughly 1 in 5 Americans report some lifetime involvement in consensual non-monogamy, while only 2.5% to 4% of people in relationships are practicing it at any given moment.
Mating in Captivity by Esther Perel
Esther Perel published this in 2006 and it has since been translated into 24 languages. Her thesis is that the conditions producing love and the conditions producing desire work against each other. Closeness, predictability, and emotional safety build one and quietly erode the other. Perel refuses to treat this as a fault in any particular couple. She calls it a paradox to manage, which frustrates readers who want a procedure. Her advice is mostly about restoring distance, since she argues that desire needs some space to travel across and that couples who merge completely have removed it. The book is short on studies and long on case material from her practice, so it works best alongside the research-heavy titles on this list.
Untrue by Wednesday Martin
Untrue, published in 2018, spends its length on one reversal. The evidence on female fidelity runs opposite to the assumption most readers carry, and Wednesday Martin, an anthropologist with a Yale doctorate, builds the case from survey data rather than from argument alone.
Her strongest material concerns boredom. Working with researcher Kristen Mark on a sample of 3,341 people in committed relationships, she found that half described themselves as bored or close to it, and that women were twice as likely as men to report boredom in the first year. Martin also cites the finding that married women were 40% more likely to seek sex outside the marriage in 2010 than in 1990.
The book is openly polemical, but the research it collects on female infidelity is not easily dismissed.
Date-onomics by Jon Birger
Date-onomics treats the dating market as a market, with supply and pricing power. Jon Birger, a business journalist, published it in 2015. Among Americans aged 22 to 29, Census figures showed 5.5 million college-educated women against 4.1 million college-educated men, a ratio of roughly 4 to 3.
His claim is that behavior follows the ratio. Where women outnumber men in a given pool, courtship gets shorter and commitment gets rarer, and the pattern shows up in historical populations long before anyone had a phone. The book gives educated women a structural explanation for something usually blamed on personal failure, and its practical advice follows directly from the numbers. Birger tells college-educated women to consider cities where the ratio runs the other way, and to stop treating a degree as a filter, since the shortage he describes exists only inside that filter.
Where to Start
Read Buss and Finkel together first. One explains what people want, the other explains what they now demand from a single relationship, and the friction between the two accounts explains most modern relationship trouble. Add Perel when the trouble is about desire, and Levine and Heller when it is about the pattern of one person chasing and one person retreating.
The harder question comes after the reading of these books about Modern Relationships. If mate preferences are as stable as Buss says and expectations of a partner are as high as Finkel says, what does a person do with the gap between them? None of these seven authors answer that, and the fact that people who have absorbed all this research still get their attachment style wrong in practice suggests the answer is not in a book at all.
