diff --git a/sum_square_difference/main.go b/06_sum_square_difference/main.go
similarity index 100%
rename from sum_square_difference/main.go
rename to 06_sum_square_difference/main.go
diff --git a/sum_square_difference/sum_square_difference_test.go b/06_sum_square_difference/sum_square_difference_test.go
similarity index 100%
rename from sum_square_difference/sum_square_difference_test.go
rename to 06_sum_square_difference/sum_square_difference_test.go
diff --git a/10001st_prime/main.go b/07_10001st_prime/main.go
similarity index 100%
rename from 10001st_prime/main.go
rename to 07_10001st_prime/main.go
diff --git a/largest_product_in_a_series/largest_product_test.go b/08_largest_product_in_a_series/largest_product_test.go
similarity index 100%
rename from largest_product_in_a_series/largest_product_test.go
rename to 08_largest_product_in_a_series/largest_product_test.go
diff --git a/largest_product_in_a_series/main.go b/08_largest_product_in_a_series/main.go
similarity index 100%
rename from largest_product_in_a_series/main.go
rename to 08_largest_product_in_a_series/main.go
diff --git a/special_dpythagorean_triplet/main.go b/09_special_dpythagorean_triplet/main.go
similarity index 100%
rename from special_dpythagorean_triplet/main.go
rename to 09_special_dpythagorean_triplet/main.go
diff --git a/special_dpythagorean_triplet/special_pythagorean_triplet_test.go b/09_special_dpythagorean_triplet/special_pythagorean_triplet_test.go
similarity index 100%
rename from special_dpythagorean_triplet/special_pythagorean_triplet_test.go
rename to 09_special_dpythagorean_triplet/special_pythagorean_triplet_test.go
diff --git a/summation_of_primes/main.go b/10_summation_of_primes/main.go
similarity index 100%
rename from summation_of_primes/main.go
rename to 10_summation_of_primes/main.go
diff --git a/summation_of_primes/summation_of_primes_test.go b/10_summation_of_primes/summation_of_primes_test.go
similarity index 100%
rename from summation_of_primes/summation_of_primes_test.go
rename to 10_summation_of_primes/summation_of_primes_test.go
diff --git a/largest_product_in_grid/digits.txt b/11_largest_product_in_grid/digits.txt
similarity index 100%
rename from largest_product_in_grid/digits.txt
rename to 11_largest_product_in_grid/digits.txt
diff --git a/largest_product_in_grid/largest_product_test.go b/11_largest_product_in_grid/largest_product_test.go
similarity index 100%
rename from largest_product_in_grid/largest_product_test.go
rename to 11_largest_product_in_grid/largest_product_test.go
diff --git a/largest_product_in_grid/main.go b/11_largest_product_in_grid/main.go
similarity index 100%
rename from largest_product_in_grid/main.go
rename to 11_largest_product_in_grid/main.go
diff --git a/highly_divisible_triangular_number/main.go b/12_highly_divisible_triangular_number/main.go
similarity index 100%
rename from highly_divisible_triangular_number/main.go
rename to 12_highly_divisible_triangular_number/main.go
diff --git a/highly_divisible_triangular_number/triangular_number_test.go b/12_highly_divisible_triangular_number/triangular_number_test.go
similarity index 100%
rename from highly_divisible_triangular_number/triangular_number_test.go
rename to 12_highly_divisible_triangular_number/triangular_number_test.go
diff --git a/large_sum/digits.txt b/13_large_sum/digits.txt
similarity index 100%
rename from large_sum/digits.txt
rename to 13_large_sum/digits.txt
diff --git a/large_sum/main.go b/13_large_sum/main.go
similarity index 100%
rename from large_sum/main.go
rename to 13_large_sum/main.go
diff --git a/longest_collatz_sequence/collatz_test.go b/14_longest_collatz_sequence/collatz_test.go
similarity index 100%
rename from longest_collatz_sequence/collatz_test.go
rename to 14_longest_collatz_sequence/collatz_test.go
diff --git a/longest_collatz_sequence/main.go b/14_longest_collatz_sequence/main.go
similarity index 100%
rename from longest_collatz_sequence/main.go
rename to 14_longest_collatz_sequence/main.go