diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6140beae28..2693ea97b2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@ Next Release
 #### Fixes
 
 * [#492](https://github.com/intridea/grape/pull/492): Don't allow to have nil value when a param is required and has a list of allowed values. - [@Antti](https://github.com/Antti)
+* [#495](https://github.com/intridea/grape/pull/495): Fix `ParamsScope#params` for parameters nested inside arrays - [@asross](https://github.com/asross).
 
 0.6.1
 =====
diff --git a/lib/grape/validations.rb b/lib/grape/validations.rb
index 7dd9a8d4e8..d079449c1b 100644
--- a/lib/grape/validations.rb
+++ b/lib/grape/validations.rb
@@ -102,7 +102,7 @@ def initialize(opts, &block)
       end
 
       def should_validate?(parameters)
-        return false if @optional && params(parameters).blank?
+        return false if @optional && params(parameters).all?(&:blank?)
         return true if parent.nil?
         parent.should_validate?(parameters)
       end
@@ -133,7 +133,13 @@ def group(element, &block)
 
       def params(params)
         params = @parent.params(params) if @parent
-        params = params[@element] || {} if @element
+        if @element
+          if params.is_a?(Array)
+            params = params.map { |el| el[@element] || {} }
+          else
+            params = params[@element] || {}
+          end
+        end
         params
       end
 
diff --git a/spec/grape/validations_spec.rb b/spec/grape/validations_spec.rb
index 0f35268733..6c5302f21a 100644
--- a/spec/grape/validations_spec.rb
+++ b/spec/grape/validations_spec.rb
@@ -156,6 +156,49 @@ def app
       end
     end
 
+    context 'validation within arrays' do
+      before do
+        subject.params do
+          group :children do
+            requires :name
+            group :mother do
+              requires :name
+            end
+          end
+        end
+        subject.get '/within_array' do
+          'within array works'
+        end
+      end
+
+      it 'can handle new scopes within child elements' do
+        get '/within_array', children: [
+          { name: 'John', mother: { name: 'Jane' } },
+          { name: 'Joe', mother: { name: 'Josie' } }
+        ]
+        last_response.status.should == 200
+        last_response.body.should == 'within array works'
+      end
+
+      it 'errors when a parameter is not present' do
+        get '/within_array', children: [
+          { name: 'Jim', mother: {} },
+          { name: 'Job', mother: { name: 'Joy' } }
+        ]
+        last_response.status.should == 400
+        last_response.body.should == 'children[mother][name] is missing'
+      end
+
+      it 'safely handles empty arrays and blank parameters' do
+        get '/within_array', children: []
+        last_response.status.should == 400
+        last_response.body.should == 'children[name] is missing, children[mother][name] is missing'
+        get '/within_array', children: [name: 'Jay']
+        last_response.status.should == 400
+        last_response.body.should == 'children[mother][name] is missing'
+      end
+    end
+
     context 'optional with a block' do
       before do
         subject.params do
@@ -234,6 +277,20 @@ def app
         last_response.body.should == 'nested optional group works'
       end
 
+      it 'handles validation within arrays' do
+        get '/nested_optional_group', items: [key: 'foo']
+        last_response.status.should == 400
+        last_response.body.should == 'items[required_subitems][value] is missing'
+
+        get '/nested_optional_group', items: [key: 'foo', required_subitems: { value: 'bar' }]
+        last_response.status.should == 200
+        last_response.body.should == 'nested optional group works'
+
+        get '/nested_optional_group', items: [key: 'foo', required_subitems: { value: 'bar' }, optional_subitems: { not_value: 'baz' }]
+        last_response.status.should == 400
+        last_response.body.should == 'items[optional_subitems][value] is missing'
+      end
+
       it 'adds to declared parameters' do
         subject.params do
           optional :items do