Here is the full list of all 27 Dreamwalker: Never Fall Asleep achievements.
Find 16 Dreamer's Sheep.
Find the book about the Nightmare.
Save Hellen from the car wreckage.
Escape the carriage.
Watch all the cutscenes from the first hour of the game.
Get into the Tower.
Find Sandra's diary.
Finish three Minigames in a row without skipping.
Confront Sandra's trauma.
Complete any Hidden Object Puzzle without using a hint.
Find 3 Hidden Objects in 3 seconds.
Finish a Minigame in less than 1 minute.
Find your first Dreamer's Sheep.
Find 32 Dreamer's Sheep.
Finish all Minigames without skipping.
Complete 3 Hidden Object Puzzles with no more than 5 mistakes in each one.
Finish any Hidden Object Puzzle in less than 30 seconds.
Complete all Hidden Object Puzzles without using a hint.
Break into the mayor's cabinet.
Escape the prison cell.
Find the hard evidence.
Get to Allan's atelier.
Record the murderer's confession.
Release Sandra from the Nightmare.
Read all the notes placed throughout the game.
Finish all Meditation Minigames without skipping.
Collect all Postcards and Stamps.