diff --git a/lib/ransack/adapters/active_record/context.rb b/lib/ransack/adapters/active_record/context.rb
index c55257b..8acf896 100644
--- a/lib/ransack/adapters/active_record/context.rb
+++ b/lib/ransack/adapters/active_record/context.rb
@@ -47,6 +47,10 @@ module Ransack
                   scope_or_sort = scope_or_sort.direction == :asc ? Arel.sql("#{scope_or_sort.to_sql} NULLS FIRST") : Arel.sql("#{scope_or_sort.to_sql} NULLS LAST")
                 when :nulls_last
                   scope_or_sort = scope_or_sort.direction == :asc ? Arel.sql("#{scope_or_sort.to_sql} NULLS LAST") : Arel.sql("#{scope_or_sort.to_sql} NULLS FIRST")
+                when :nulls_always_first
+                  scope_or_sort = Arel.sql("#{scope_or_sort.to_sql} NULLS FIRST")
+                when :nulls_always_last
+                  scope_or_sort = Arel.sql("#{scope_or_sort.to_sql} NULLS LAST")
                 end
 
                 relation = relation.order(scope_or_sort)
diff --git a/lib/ransack/configuration.rb b/lib/ransack/configuration.rb
index 4347db5..1ca0434 100644
--- a/lib/ransack/configuration.rb
+++ b/lib/ransack/configuration.rb
@@ -149,7 +149,7 @@ module Ransack
     # User may want to configure it like this:
     #
     # Ransack.configure do |c|
-    #   c.postgres_fields_sort_option = :nulls_first # or :nulls_last
+    #   c.postgres_fields_sort_option = :nulls_first # or e.g. :nulls_always_last
     # end
     #
     # See this feature: https://www.postgresql.org/docs/13/queries-order.html
diff --git a/spec/ransack/search_spec.rb b/spec/ransack/search_spec.rb
index e66c2e5..99adb05 100644
--- a/spec/ransack/search_spec.rb
+++ b/spec/ransack/search_spec.rb
@@ -605,6 +605,18 @@ module Ransack
         s = Search.new(Person, s: 'doubled_name desc')
         expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" DESC NULLS FIRST"
 
+        Ransack.configure { |c| c.postgres_fields_sort_option = :nulls_always_first }
+        s = Search.new(Person, s: 'doubled_name asc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" ASC NULLS FIRST"
+        s = Search.new(Person, s: 'doubled_name desc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" DESC NULLS FIRST"
+
+        Ransack.configure { |c| c.postgres_fields_sort_option = :nulls_always_last }
+        s = Search.new(Person, s: 'doubled_name asc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" ASC NULLS LAST"
+        s = Search.new(Person, s: 'doubled_name desc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" DESC NULLS LAST"
+
         Ransack.options = default
       end
     end