--- title: "Ferber Method: Intervals, Timeline and What the Evidence Shows | Dalo Baby" description: "The interval schedule, what happens night by night, and what randomised trials found about infant cortisol, attachment at 12 months and outcomes five years later." canonical: https://dalofamilyapps.com/learn/sleep/ferber-method --- [Home](/)/[Knowledge Hub](/learn)/[Sleep](/learn/sleep) # The Ferber method: intervals, timeline and what the evidence shows [Dalo Baby Editorial](/learn/editorial-policy)Published September 4, 2026Last reviewed September 4, 20266 min read The Ferber method is graduated extinction: you put the baby down awake and return at lengthening intervals to reassure briefly without picking up. An AASM review of 52 studies found 94% reported efficacy. A randomised trial measuring cortisol found infant stress fell, with no attachment differences at twelve months. ![The Ferber method: intervals, timeline and what the evidence shows](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2Fb1ca8afb24ddd4867a003f21634e57f3713cfc54-1376x768.jpg%3Frect%3D176%2C0%2C1024%2C768%26w%3D800%26h%3D600%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ## Key takeaways - The Ferber method is graduated extinction — search that name and you find randomised trials instead of opinion. - An AASM review of 52 studies: 94% reported behavioural interventions were efficacious, over 80% of children improved and held it 3–6 months. - In a randomised trial measuring salivary cortisol, infant stress declined rather than rose, and there were no attachment or behaviour differences at 12 months. - A five-year follow-up of 326 children found no differences on any outcome — no lasting harm, and no lasting benefit either. - Intervals lengthen across the night and across the week; expect night one to be worst and a setback around night three or four. In this article 1. [What it actually is](#what-it-actually-is) 2. [What the evidence supports](#what-the-evidence-supports) 3. [The harm question, answered properly](#the-harm-question-answered-properly) 4. [Before you start](#before-you-start) 5. [The intervals](#the-intervals) 6. [What actually happens](#what-actually-happens) 7. [When it is the wrong method](#when-it-is-the-wrong-method) 8. [The honest summary](#the-honest-summary) The Ferber method is the most argued-about technique in baby sleep and one of the few with a genuine evidence base behind it — though not under that name. In the literature it is graduated extinction, and almost everything worth knowing about it comes from trials that never mention Ferber at all. ## What it actually is You put your baby down awake, leave, and return at progressively longer intervals to reassure them briefly without picking them up or feeding them. Richard Ferber called it progressive waiting; researchers call it graduated extinction. The word extinction is behavioural jargon for removing the response that maintains a behaviour — here, the settling help — not a description of what it is like to do. One name, two vocabularies If you go looking for evidence on "the Ferber method" you will find opinion. If you look for graduated extinction you will find randomised trials, a systematic review of 52 studies and a set of formal practice parameters. They are the same intervention. This page uses the research where the research exists. ## What the evidence supports The American Academy of Sleep Medicine's task force reviewed 52 treatment studies. Across all of them, 94% reported that behavioural interventions were efficacious, with over 80% of treated children showing clinically significant improvement maintained for three to six months. Graduated extinction is one of the specific therapies the review supports.[\[3\]](#ref-mind) Those findings were turned into formal practice parameters for children from birth to just under five years.[\[4\]](#ref-pp) 94% / 80% of 52 studies reported behavioural sleep interventions were efficacious; over 80% of treated children improved and held it for 3–6 months (AASM review, 2006)[\[3\]](#ref-mind) ## The harm question, answered properly This is the part parents actually want, so it is worth being precise rather than reassuring. A randomised trial put 43 infants aged 6 to 16 months into graduated extinction, bedtime fading or a sleep-education control, and measured infant stress directly through morning and afternoon salivary cortisol rather than by asking parents how it felt.[\[1\]](#ref-grad) Cortisol showed small-to-moderate **declines** in the graduated extinction group compared with controls — stress went down, not up. Twelve months later the children were assessed for emotional and behavioural problems, and the mother-child pairs went through the strange situation procedure to measure attachment. There were no significant differences between the groups on either.[\[1\]](#ref-grad) A separate trial followed 326 children to age six, five years after a behavioural sleep programme delivered at eight to ten months. It found no evidence of differences between intervention and control families on any outcome measured: child mental health, sleep, psychosocial functioning, chronic stress, child-parent closeness or conflict, attachment, or parental depression and anxiety.[\[2\]](#ref-price) The authors' conclusion is worth quoting in both directions — behavioural sleep techniques have no marked long-lasting effects, positive or negative. Both claims are overstated The five-year follow-up is as much a check on the enthusiasm as on the fear. It found no lasting harm, which answers the common worry. It also found no lasting benefit, which means anyone promising that sleep training will change your child's development is going beyond the evidence too. What it buys is short- to medium-term relief, and that is a real thing to want. ## Before you start - Age. Trials in this area recruit from around six months. Below that there is no evidence base and a lot of feeding still to do. - Safe sleep first. Own clear, flat sleep space, on the back, nothing in the cot. This is non-negotiable and unrelated to method. - Not while ill, teething badly, or in the week of a house move or nursery start. - Feeds decided in advance. Know which night feeds you are keeping, so you are not making that call at 2am. - Both adults agreed. The method fails on inconsistency more than on anything else. - The day sorted first. If the last stretch before bed is wrong, no night-time method will hold — check [wake window stacking](/learn/sleep/wake-window-stacking) before you start. ## The intervals Ferber's book gives a grid of progressive waiting times. The exact numbers are not magic and the trials used their own — what matters is that the intervals lengthen, and that they are the same every time within a night. Night First wait Second Third and after 1 3 5 10 2 5 10 12 3 10 12 15 4 12 15 17 5 15 17 20 6 17 20 25 7 20 25 30 A typical progressive-waiting schedule, in minutes ### How a night runs Keep the check-ins short and boring. The point of going in is to reassure you both that nothing is wrong, not to settle the baby — the settling is the part they are learning to do. 1. 1 Full bedtime routine, then down awake Drowsy but genuinely awake. If your baby is asleep when they hit the mattress, there is nothing for them to practise. 2. 2 Leave, and start the clock Wait the first interval. Time it on a phone rather than by feel — distress makes three minutes feel like fifteen. 3. 3 Go in for under a minute Lights low, a few words, a hand on the chest if that helps. Do not pick up, do not feed, do not turn it into a conversation. 4. 4 Leave again and lengthen the interval Repeat with the next number on the row. Keep going until your baby is asleep. 5. 5 Use the same row for every waking that night Restart at the first interval after each waking. Move to the next row tomorrow. 6. 6 Do the planned night feeds normally A feed you decided to keep is a feed, not a failure. Do it calmly, then back to the intervals. ## What actually happens Night one is usually the worst and often much worse than parents expect. Nights two and three commonly get better. Night three or four frequently gets worse again before it improves — an extinction burst, which is the behaviour being tested rather than the method failing. Most families who see it through describe a working pattern inside a week to ten days. Expect regressions after illness, travel and developmental leaps. A rerun usually takes two or three nights rather than a full week, and that is normal rather than a sign the first attempt did not take. ## When it is the wrong method Graduated extinction is not the only supported option, and it is not the best fit for every baby. A trial of 91 infants aged 9 to 18 months compared checking-in — graduated extinction, with gradual separation — against camping-out, where a parent stays in the room. Both improved sleep and held it at six months, but infant separation anxiety moderated which one worked better: infants with high separation anxiety benefited more from camping-out.[\[5\]](#ref-kahn) If your baby is at the anxious end, [the chair method](/learn/sleep/chair-method) is the evidence-based alternative rather than the soft option. - You cannot tolerate the crying. That is a legitimate reason, not a character flaw, and there are methods that do not require it. - Your baby has high separation anxiety, where the trial evidence points elsewhere. - Bedtime is the only problem and night wakings are fine — [bedtime fading](/learn/sleep/bedtime-fading) targets that directly and involves no crying. - Nothing has improved after two weeks of genuine consistency. That usually means the schedule, not the method. ![](/_next/image?url=%2Fimages%2Fnap-plan-icon.webp&w=256&q=75&dpl=dpl_HDQuuA58EiAncPne4fumhEvNhdFC) Dalo Sleep Time the intervals so you do not have to Dalo Sleep runs the interval timer, logs each check-in and each waking, and shows the week as a chart — so "is this actually working?" is a question you answer from data rather than from how last night felt. [Dalo Sleep](/apps/dalo-sleep) ## The honest summary Graduated extinction works for most families in the short to medium term, does not appear to raise infant stress hormones, and leaves no measurable trace on attachment or behaviour at twelve months or at five years. It is also not the only thing that works, it is unpleasant for several nights, and a good proportion of infant sleep problems improve on their own — in one trial the control group had caught up by four months.[\[6\]](#ref-hw) Knowing that should make the decision easier in both directions.[\[7\]](#ref-sl1) In this article 1. [What it actually is](#what-it-actually-is) 2. [What the evidence supports](#what-the-evidence-supports) 3. [The harm question, answered properly](#the-harm-question-answered-properly) 4. [Before you start](#before-you-start) 5. [The intervals](#the-intervals) 6. [What actually happens](#what-actually-happens) 7. [When it is the wrong method](#when-it-is-the-wrong-method) 8. [The honest summary](#the-honest-summary) ## References & disclaimer We link every source we used. Where guidance differs by country, we cite the authority that applies where you are. 1. 1. [Behavioral Interventions for Infant Sleep Problems: A Randomized Controlled Trial](https://pubmed.ncbi.nlm.nih.gov/27221288/) Pediatrics (AAP) · 2016 · Study 2. 2. [Five-year follow-up of harms and benefits of behavioral infant sleep intervention: randomized trial](https://pubmed.ncbi.nlm.nih.gov/22966034/) Pediatrics (AAP) · 2012 · Study 3. 3. [Behavioral treatment of bedtime problems and night wakings in infants and young children](https://pubmed.ncbi.nlm.nih.gov/17068979/) Sleep (American Academy of Sleep Medicine) · 2006 · Review 4. 4. [Practice parameters for behavioral treatment of bedtime problems and night wakings in infants and young children](https://pubmed.ncbi.nlm.nih.gov/17068980/) Sleep (American Academy of Sleep Medicine) · 2006 · Guideline 5. 5. [Behavioral interventions for pediatric insomnia: one treatment may not fit all](https://pubmed.ncbi.nlm.nih.gov/31676910/) Sleep (Sleep Research Society) · 2020 · Study 6. 6. [Randomised controlled trial of behavioural infant sleep intervention to improve infant sleep and maternal mood](https://pubmed.ncbi.nlm.nih.gov/11991909/) BMJ · 2002 · Study 7. 7. [Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement](https://jcsm.aasm.org/doi/full/10.5664/jcsm.5866) Journal of Clinical Sleep Medicine (AASM) · 2016 · Guideline 8. 8. [Baby sleep patterns](https://www.lullabytrust.org.uk/baby-safety/being-a-parent-or-caregiver/baby-sleep-patterns/) The Lullaby Trust · Organisation * * * Before you act on this Sleep training is a choice, not a requirement. This guide describes how a method works and what the evidence does and does not show. No method suits every family, and choosing not to use one is an equally valid decision. If your baby's sleep is worrying you, speak to your health visitor or paediatrician. ## Questions, answered Is the Ferber method harmful? The evidence does not support that. A randomised trial measuring salivary cortisol found infant stress declined rather than rose, with no attachment or behaviour differences twelve months later. A separate five-year follow-up of 326 children found no differences on any outcome measured. At what age can you start the Ferber method? The trials in this area recruit infants from around six months, so that is the age below which there is no evidence base to draw on. Age is not the only gate: safe sleep, a settled daytime schedule, agreement between both adults, and a decision in advance about which night feeds you are keeping all matter more than the exact month. How long does the Ferber method take to work? Most families who see it through describe a working pattern within a week to ten days. Night one is usually the worst, nights two and three often improve, and night three or four frequently gets worse again — an extinction burst, which is the behaviour being tested rather than the method failing. Do I have to drop night feeds to do Ferber? No, but you should decide in advance which ones you are keeping. The method is about how your baby returns to sleep, not about calories. What causes trouble is making the decision at 2am, because inconsistency is what this approach fails on more than anything else. ![Dalo Sleep](/_next/image?url=%2Fimages%2Fnap-plan-icon.webp&w=128&q=75&dpl=dpl_HDQuuA58EiAncPne4fumhEvNhdFC) Get it on your phone Dalo Sleep [Dalo Sleep](/apps/dalo-sleep) Part of [Baby sleep schedules and wake windows: 0–24 months](/learn/sleep/baby-sleep-schedules-and-wake-windows) ## Keep reading [ ![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F343a6209694428529f2e909c632df5cd061760d9-1376x768.jpg%3Frect%3D7%2C0%2C1363%2C768%26w%3D440%26h%3D248%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ### The chair method: gentle sleep training, step by step In the research it is called camping out, and one trial of 91 infants found it beat graduated extinction for babies with high separation anxiety. The chair schedule, and how to keep the fade moving. ](/learn/sleep/chair-method)[ ![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F82e02aecc9d0a96177cbb0aadf2f2b74de87d4dd-1376x768.jpg%3Frect%3D7%2C0%2C1363%2C768%26w%3D440%26h%3D248%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ### Bedtime fading: fixing a bedtime that is too early An hour of bedtime protest usually means bedtime is too early, not that your baby resists sleep. Measure the real sleep-onset time, start there, and walk it back — the supported method with almost no crying in it. ](/learn/sleep/bedtime-fading)[ ![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F4040cb604782bc0058db4d4e95796f4d22ff5adc-1376x768.jpg%3Frect%3D7%2C0%2C1363%2C768%26w%3D440%26h%3D248%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ### Sleep training methods compared, without the judgment Parents choose between branded methods; researchers test behavioural categories. Mapping one to the other — plus what the trials actually found on harm, and a decision rule that is about your baby. ](/learn/sleep/sleep-training-methods-compared)[ ![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F578eb7b0a50d77606876dc160b56e3e46e07dd4a-1376x768.jpg%3Frect%3D7%2C0%2C1363%2C768%26w%3D440%26h%3D248%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ### Wake window stacking: why the last one should be longest Wake windows across a day are not equal. Sleep pressure builds with time awake, so the stretch before bed decides how the night goes — and it should be the longest of the day. ](/learn/sleep/wake-window-stacking) ## Try the free tools - [Baby wake window calculator](/tools/wake-window-calculator) ## Development milestones - [6-9 months](/learn/milestones/6-9-months) - [9-12 months](/learn/milestones/9-12-months) [← All sleep guides](/learn/sleep) [Read as Markdown](/api/markdown?path=%2Flearn%2Fsleep%2Fferber-method)