diff --git a/app/controllers/rails_admin/main_controller.rb b/app/controllers/rails_admin/main_controller.rb
index afc68ff8f3..815b098cb7 100644
--- a/app/controllers/rails_admin/main_controller.rb
+++ b/app/controllers/rails_admin/main_controller.rb
@@ -90,9 +90,7 @@ def redirect_to_on_success
     def sanitize_params_for!(action, model_config = @model_config, target_params = params[@abstract_model.param_key])
       return unless target_params.present?
       fields = model_config.send(action).with(controller: self, view: view_context, object: @object).visible_fields
-      allowed_methods = fields.collect do|f|
-        f.allowed_methods
-      end.flatten.uniq.collect(&:to_s) << 'id' << '_destroy'
+      allowed_methods = fields.collect(&:allowed_methods).flatten.uniq.collect(&:to_s) << 'id' << '_destroy'
       fields.each { |f| f.parse_input(target_params) }
       target_params.slice!(*allowed_methods)
       target_params.permit! if target_params.respond_to?(:permit!)
diff --git a/lib/rails_admin/abstract_model.rb b/lib/rails_admin/abstract_model.rb
index ecbd5f099b..9800aa51df 100644
--- a/lib/rails_admin/abstract_model.rb
+++ b/lib/rails_admin/abstract_model.rb
@@ -27,7 +27,7 @@ def new(m)
       def polymorphic_parents(adapter, model_name, name)
         @@polymorphic_parents[adapter.to_sym] ||= {}.tap do |hash|
           all(adapter).each do |am|
-            am.associations.select { |r| r.as }.each do |association|
+            am.associations.select(&:as).each do |association|
               (hash[[association.klass.to_s.underscore, association.as].join('_').to_sym] ||= []) << am.model
             end
           end
diff --git a/lib/rails_admin/config/fields/base.rb b/lib/rails_admin/config/fields/base.rb
index 15637d769f..91c5484e9a 100644
--- a/lib/rails_admin/config/fields/base.rb
+++ b/lib/rails_admin/config/fields/base.rb
@@ -152,7 +152,7 @@ def virtual?
         # Accessor for field's length restrictions per validations
         #
         register_instance_option :valid_length do
-          @valid_length ||= abstract_model.model.validators_on(name).detect { |v| v.kind == :length }.try { |v| v.options } || {}
+          @valid_length ||= abstract_model.model.validators_on(name).detect { |v| v.kind == :length }.try(&:options) || {}
         end
 
         register_instance_option :partial do
diff --git a/lib/rails_admin/config/fields/types/belongs_to_association.rb b/lib/rails_admin/config/fields/types/belongs_to_association.rb
index 5d048610b2..2899f19c83 100644
--- a/lib/rails_admin/config/fields/types/belongs_to_association.rb
+++ b/lib/rails_admin/config/fields/types/belongs_to_association.rb
@@ -12,11 +12,11 @@ class BelongsToAssociation < RailsAdmin::Config::Fields::Association
           end
 
           register_instance_option :sortable do
-            @sortable ||= abstract_model.adapter_supports_joins? && associated_model_config.abstract_model.properties.collect { |p| p.name }.include?(associated_model_config.object_label_method) ? associated_model_config.object_label_method : {abstract_model.table_name => method_name}
+            @sortable ||= abstract_model.adapter_supports_joins? && associated_model_config.abstract_model.properties.collect(&:name).include?(associated_model_config.object_label_method) ? associated_model_config.object_label_method : {abstract_model.table_name => method_name}
           end
 
           register_instance_option :searchable do
-            @searchable ||= associated_model_config.abstract_model.properties.collect { |p| p.name }.include?(associated_model_config.object_label_method) ? [associated_model_config.object_label_method, {abstract_model.model => method_name}] : {abstract_model.model => method_name}
+            @searchable ||= associated_model_config.abstract_model.properties.collect(&:name).include?(associated_model_config.object_label_method) ? [associated_model_config.object_label_method, {abstract_model.model => method_name}] : {abstract_model.model => method_name}
           end
 
           register_instance_option :partial do
diff --git a/lib/rails_admin/config/has_fields.rb b/lib/rails_admin/config/has_fields.rb
index c247805864..5957c7cde4 100644
--- a/lib/rails_admin/config/has_fields.rb
+++ b/lib/rails_admin/config/has_fields.rb
@@ -83,7 +83,7 @@ def fields(*field_names, &block)
         return all_fields if field_names.empty? && !block
 
         if field_names.empty?
-          defined = _fields.select { |f| f.defined }
+          defined = _fields.select(&:defined)
           defined = _fields if defined.empty?
         else
           defined = field_names.collect { |field_name| _fields.detect { |f| f.name == field_name } }
diff --git a/spec/dummy_app/app/active_record/team.rb b/spec/dummy_app/app/active_record/team.rb
index 7cb3f110e9..f5e31c4437 100644
--- a/spec/dummy_app/app/active_record/team.rb
+++ b/spec/dummy_app/app/active_record/team.rb
@@ -15,7 +15,7 @@ class Team < ActiveRecord::Base
   belongs_to :division
 
   def player_names_truncated
-    players.collect { |p| p.name }.join(', ')[0..32]
+    players.collect(&:name).join(', ')[0..32]
   end
 
   def color_enum
diff --git a/spec/dummy_app/app/mongoid/team.rb b/spec/dummy_app/app/mongoid/team.rb
index 8ea92ecd47..a82bcf0a53 100644
--- a/spec/dummy_app/app/mongoid/team.rb
+++ b/spec/dummy_app/app/mongoid/team.rb
@@ -36,7 +36,7 @@ class Team
   validates_length_of :mascot, maximum: 100
 
   def player_names_truncated
-    players.collect { |p| p.name }.join(', ')[0..32]
+    players.collect(&:name).join(', ')[0..32]
   end
 
   def color_enum
diff --git a/spec/orm/active_record.rb b/spec/orm/active_record.rb
index 81ea328e79..c00801b6e3 100644
--- a/spec/orm/active_record.rb
+++ b/spec/orm/active_record.rb
@@ -27,7 +27,7 @@ def columns_hash
     end
 
     def column_names
-      @column_names ||= columns.collect { |column| column.name }
+      @column_names ||= columns.collect(&:name)
     end
 
     def column_defaults
diff --git a/spec/rails_admin/adapters/active_record/association_spec.rb b/spec/rails_admin/adapters/active_record/association_spec.rb
index 9a643f5f27..60e378e674 100644
--- a/spec/rails_admin/adapters/active_record/association_spec.rb
+++ b/spec/rails_admin/adapters/active_record/association_spec.rb
@@ -54,7 +54,7 @@ class ARComment < ActiveRecord::Base
 
   it 'list associations types in supported [:belongs_to, :has_and_belongs_to_many, :has_many, :has_one]' do
     # ActiveRecord 4.1 converts has_and_belongs_to_many association to has_many
-    expect((@post.associations + @blog.associations + @user.associations).collect { |a| a.type }.uniq.collect(&:to_s)).to include(*%w(belongs_to has_many has_one))
+    expect((@post.associations + @blog.associations + @user.associations).collect(&:type).uniq.collect(&:to_s)).to include(*%w(belongs_to has_many has_one))
   end
 
   describe 'belongs_to association' do
diff --git a/spec/rails_admin/adapters/mongoid_spec.rb b/spec/rails_admin/adapters/mongoid_spec.rb
index 25015de5f0..6c54fafa35 100644
--- a/spec/rails_admin/adapters/mongoid_spec.rb
+++ b/spec/rails_admin/adapters/mongoid_spec.rb
@@ -56,7 +56,7 @@
       end
 
       it 'supports eager loading' do
-        expect(@abstract_model.all(include: :team).inclusions.collect { |i| i.class_name }).to eq(['Team'])
+        expect(@abstract_model.all(include: :team).inclusions.collect(&:class_name)).to eq(['Team'])
       end
 
       it 'supports limiting' do
diff --git a/spec/rails_admin/config/fields/base_spec.rb b/spec/rails_admin/config/fields/base_spec.rb
index 5ab85e3731..02a42f2bf1 100644
--- a/spec/rails_admin/config/fields/base_spec.rb
+++ b/spec/rails_admin/config/fields/base_spec.rb
@@ -379,10 +379,10 @@ class FieldVisibilityTest < Tableless
         column :updated_on, :datetime
         column :deleted_on, :datetime
       end
-      expect(RailsAdmin.config(FieldVisibilityTest).base.fields.select { |f| f.visible? }.collect(&:name)).to match_array [:_id, :created_at, :created_on, :deleted_at, :deleted_on, :id, :name, :updated_at, :updated_on]
-      expect(RailsAdmin.config(FieldVisibilityTest).list.fields.select { |f| f.visible? }.collect(&:name)).to match_array [:_id, :created_at, :created_on, :deleted_at, :deleted_on, :id, :name, :updated_at, :updated_on]
-      expect(RailsAdmin.config(FieldVisibilityTest).edit.fields.select { |f| f.visible? }.collect(&:name)).to match_array [:name]
-      expect(RailsAdmin.config(FieldVisibilityTest).show.fields.select { |f| f.visible? }.collect(&:name)).to match_array [:name]
+      expect(RailsAdmin.config(FieldVisibilityTest).base.fields.select(&:visible?).collect(&:name)).to match_array [:_id, :created_at, :created_on, :deleted_at, :deleted_on, :id, :name, :updated_at, :updated_on]
+      expect(RailsAdmin.config(FieldVisibilityTest).list.fields.select(&:visible?).collect(&:name)).to match_array [:_id, :created_at, :created_on, :deleted_at, :deleted_on, :id, :name, :updated_at, :updated_on]
+      expect(RailsAdmin.config(FieldVisibilityTest).edit.fields.select(&:visible?).collect(&:name)).to match_array [:name]
+      expect(RailsAdmin.config(FieldVisibilityTest).show.fields.select(&:visible?).collect(&:name)).to match_array [:name]
     end
   end