diff --git a/src/converters/xml.cr b/src/converters/xml.cr
index 907d76b..2b27a29 100644
--- a/src/converters/xml.cr
+++ b/src/converters/xml.cr
@@ -19,6 +19,8 @@ module OQ::Converters::XML
     builder = ::JSON::Builder.new output
     xml = ::XML::Reader.new input
 
+    xmlns = self.parse_deserialize_args args
+
     # Set reader to first element
     xml.read
 
@@ -32,26 +34,27 @@ module OQ::Converters::XML
           xml.read
         end
 
-        process_element_node xml.expand, builder
+        process_element_node xml.expand, builder, xmlns: xmlns
       end
     end
   end
 
-  private def self.process_element_node(node : ::XML::Node, builder : ::JSON::Builder) : Nil
+  private def self.process_element_node(node : ::XML::Node, builder : ::JSON::Builder, *, xmlns : Bool) : Nil
     # If the node doesn't have nested elements nor attributes nor a namespace; just emit a scalar value
-    if !has_nested_elements(node) && node.attributes.empty? && node.namespaces.empty?
+    # TODO: Make checking for namespaces the default behavior in oq 2.x
+    if (!has_nested_elements(node) && node.attributes.empty?) || (xmlns && node.namespace_definitions.empty?)
       return builder.field node.name, get_node_value node
     end
 
     # Otherwise process the node as a key/value pair
     builder.field self.normalize_node_name node do
       builder.object do
-        process_children node, builder
+        process_children node, builder, xmlns: xmlns
       end
     end
   end
 
-  private def self.process_array_node(name : String, children : Array(::XML::Node), builder : ::JSON::Builder) : Nil
+  private def self.process_array_node(name : String, children : Array(::XML::Node), builder : ::JSON::Builder, *, xmlns : Bool) : Nil
     builder.field name do
       builder.array do
         children.each do |node|
@@ -61,7 +64,7 @@ module OQ::Converters::XML
           else
             # Otherwise process the node within an object
             builder.object do
-              process_children node, builder
+              process_children node, builder, xmlns: xmlns
             end
           end
         end
@@ -69,16 +72,19 @@ module OQ::Converters::XML
     end
   end
 
-  private def self.process_children(node : ::XML::Node, builder : ::JSON::Builder) : Nil
+  private def self.process_children(node : ::XML::Node, builder : ::JSON::Builder, *, xmlns : Bool) : Nil
     # Process node attributes
     node.attributes.each do |attr|
       builder.field "@#{attr.name}", attr.content
     end
 
     # Include attributes for namespaces defined on this node
-    node.namespace_definitions.each do |ns|
-      key = ns.prefix ? "xmlns:#{ns.prefix}" : "xmlns"
-      builder.field "@#{key}", ns.href
+    # TODO: Make this the default behavior in oq 2.x
+    if xmlns
+      node.namespace_definitions.each do |ns|
+        key = ns.prefix ? "xmlns:#{ns.prefix}" : "xmlns"
+        builder.field "@#{key}", ns.href
+      end
     end
 
     # Determine how to process a node's children
@@ -95,14 +101,14 @@ module OQ::Converters::XML
 
       # Array
       if children.size > 1
-        process_array_node name, children, builder
+        process_array_node name, children, builder, xmlns: xmlns
       else
         if children.first.text?
           # node content in attribute object
           builder.field "#text", children.first.content
         else
           # Element
-          process_element_node children.first, builder
+          process_element_node children.first, builder, xmlns: xmlns
         end
       end
     end
@@ -120,10 +126,14 @@ module OQ::Converters::XML
     (namespace = node.namespace) && (prefix = namespace.prefix.presence) ? "#{prefix}:#{node.name}" : node.name
   end
 
+  private def self.parse_deserialize_args(args : NamedTuple) : Bool
+    args["xmlns"]
+  end
+
   def self.serialize(input : IO, output : IO, **args) : Nil
     json = ::JSON::PullParser.new input
     builder = ::XML::Builder.new output
-    indent, prolog, root, xml_item = self.parse_args(args)
+    indent, prolog, root, xml_item = self.parse_serialize_args args
 
     builder.indent = indent
 
@@ -140,7 +150,7 @@ module OQ::Converters::XML
     builder.flush unless prolog
   end
 
-  private def self.parse_args(args : NamedTuple) : Tuple(String, Bool, String, String)
+  private def self.parse_serialize_args(args : NamedTuple) : Tuple(String, Bool, String, String)
     {
       args["indent"],
       args["xml_prolog"],
diff --git a/src/oq.cr b/src/oq.cr
index 1645483..71b3f01 100644
--- a/src/oq.cr
+++ b/src/oq.cr
@@ -84,6 +84,8 @@ module OQ
     # If a tab for each indentation level instead of spaces.
     property tab : Bool
 
+    property? xmlns : Bool
+
     # The args that'll be passed to `jq`.
     @args : Array(String) = [] of String
 
@@ -94,7 +96,8 @@ module OQ
       @xml_prolog : Bool = true,
       @xml_item : String = "item",
       @indent : Int32 = 2,
-      @tab : Bool = false
+      @tab : Bool = false,
+      @xmlns : Bool = false
     )
     end
 
@@ -141,7 +144,7 @@ module OQ
         input_args.replace(input_args.map do |file_name|
           File.tempfile ".#{File.basename file_name}" do |tmp_file|
             File.open file_name do |file|
-              @input_format.converter.deserialize file, tmp_file
+              @input_format.converter.deserialize file, tmp_file, xmlns: @xmlns
             end
           end
             .tap { |tf| @tmp_files << tf }
@@ -153,7 +156,7 @@ module OQ
       end
 
       spawn do
-        @input_format.converter.deserialize input, input_write
+        @input_format.converter.deserialize input, input_write, xmlns: @xmlns
         input_write.close
         channel.send true
       rescue ex
diff --git a/src/oq_cli.cr b/src/oq_cli.cr
index 65f653d..f5337c4 100644
--- a/src/oq_cli.cr
+++ b/src/oq_cli.cr
@@ -27,10 +27,11 @@ OptionParser.parse do |parser|
   parser.on("-i FORMAT", "--input FORMAT", "Format of the input data. Supported formats: #{OQ::Format}") { |format| (f = OQ::Format.parse?(format)) ? processor.input_format = f : abort "Invalid input format: '#{format}'" }
   parser.on("-o FORMAT", "--output FORMAT", "Format of the output data. Supported formats: #{OQ::Format}") { |format| (f = OQ::Format.parse?(format)) ? processor.output_format = f : abort "Invalid output format: '#{format}'" }
   parser.on("--indent NUMBER", "Use the given number of spaces for indentation (JSON/XML only).") { |n| processor.indent = n.to_i; processor.add_arg "--indent"; processor.add_arg n }
-  parser.on("--xml-root ROOT", "Name of the root XML element if converting to XML.") { |r| processor.xml_root = r }
+  parser.on("--tab", "Use a tab for each indentation level instead of two spaces.") { processor.tab = true; processor.add_arg "--tab" }
   parser.on("--no-prolog", "Whether the XML prolog should be emitted if converting to XML.") { processor.xml_prolog = false }
   parser.on("--xml-item NAME", "The name for XML array elements without keys.") { |i| processor.xml_item = i }
-  parser.on("--tab", "Use a tab for each indentation level instead of two spaces.") { processor.tab = true; processor.add_arg "--tab" }
+  parser.on("--xmlns", "If XML namespaces should be parsed.  NOTE: This will become the default in oq 2.x.") { processor.xmlns = true }
+  parser.on("--xml-root ROOT", "Name of the root XML element if converting to XML.") { |r| processor.xml_root = r }
   parser.invalid_option { }
 end