Should socialization wait until the vaccinations are finished?

No. AVSAB's position is that the behavioral risks of under-socialization outweigh the disease risks of controlled exposure. Waiting until sixteen weeks means the window has closed.

What is a fear period?

A stretch where a puppy is unusually easily frightened. The first runs from eight to eleven weeks and coincides with going home; a second turns up somewhere between six and fourteen months. Reduce the intensity, never force it.

Why does eight weeks matter?

Bite inhibition is learned in littermate play between three and eight weeks. A puppy removed earlier misses it.

Which vaccination is the one that counts?

The last one, and it has to land after sixteen weeks. Maternal antibodies can block every earlier dose.

4Puppies are here

Puppy milestone checklist

62 milestones from birth to 18 months: what's happening, what to do about it, and who does it. The marked rows are the ones where getting it wrong has lasting consequences.

0 of 50 milestones

Marked rows are the ones where getting it wrong has lasting consequences.

Stage 1: Birth to day 3 · Days 0 to 3

Nursing within two hours of birthLastingBreeder
Birth weight recorded, per puppyBreeder
Umbilical cord dipped in iodineBreeder
Vet check within 24 to 48 hoursBreeder
Nest kept at 85 to 90°FBreeder
ID collars fitted, one per puppyBreeder

Stage 2: Week 1 to 2 · Days 4 to 14

Eyes open, around day 10 to 14Breeder
Ear canals open, around day 14Breeder
Daily weight check, gaining steadilyLastingBreeder
Room stepped down toward 80°FBreeder
Brief, gentle daily handling beginsBreeder

Stage 3: Week 3 to 4 · Days 15 to 28

Starts standing and walkingBreeder
First teeth appearBreeder
Socialization window opens, around week 3LastingBreeder
Weaning begins, gruel introducedBreeder
Play and littermate interaction increasesBreeder
Review the veterinarian-directed deworming planBreeder
Everyday household sounds introducedBreeder

Stage 4: Week 5 to 6 · Days 29 to 42

Mostly weaned onto solid foodBreeder
Bite inhibition learned in littermate playLastingBreeder
New surfaces and low obstacles introducedBreeder
Meets a range of calm, healthy peopleBreeder
Follow the veterinarian-directed deworming planBreeder
First vet visit and health checkBreeder

Stage 5: Week 7 to 8 · Days 43 to 56

Begin the veterinarian-directed vaccination scheduleLastingBreeder
First fear period, roughly 8 to 11 weeks: reduce intensity, never forceLastingNew owner
Temperament assessed for placementBreeder
Go-home age reached, not before 8 weeksLastingBreeder
Go-home kit and records preparedBreeder
Crate or pen introduced at new homeNew owner

Stage 6: Week 9 to 12 · Weeks 9 to 12

Continue vaccinations on the veterinarian's scheduleNew owner
Most socialization work happens before week 12LastingNew owner
House-training routine establishedNew owner
Name and basic cues startedNew owner
New owner's vet has seen the puppyNew owner
Short periods alone, building toleranceNew owner

Stage 7: Month 4 to 6 · Months 4 to 6

Confirm the vaccination schedule and completion with the veterinarianLastingNew owner
Socialization window effectively shut by 16 weeksLastingNew owner
Spay or neuter timing discussed with the vetNew owner
Adult teeth coming in, chewing needs increaseNew owner
Formal training or class beginsNew owner
Food step-down toward adult schedule startedNew owner

Stage 8: Month 7 to 12 · Months 7 to 12

Second fear period, somewhere between 6 and 14 monthsLastingNew owner
Adolescent independence and testing of boundariesNew owner
Approaching adult height, still filling outNew owner
Annual wellness visit scheduledNew owner

Stage 9: Month 13 to 18 · Months 13 to 18

Adult weight reached for the size classNew owner
Adult temperament largely settledNew owner
Full health check, including hips and joints for larger breedsNew owner
Adult exercise and feeding routine in placeNew owner

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General educational information and estimates only—not veterinary advice or a diagnosis. No veterinarian-client-patient relationship is created. Confirm care with a licensed veterinarian; for urgent concerns, contact a veterinarian or emergency clinic now.

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Weeks 3 to 8

Space for the socialization window

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Sights and sounds from week 3

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Puppy milestone checklist

62 milestones from birth to 18 months — what is happening, what to do about it, and who does it. The marked rows are the ones where getting it wrong has lasting consequences.

Printable

Vaccination and deworming record

Record veterinarian-directed doses and dates for each puppy to share with the new owner.

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Frequently asked

It opens at about three weeks, does most of its work before twelve, and is effectively shut by sixteen. Anything not met inside it takes far more work later.